ANCHORAGE, Alaska -- Confessed serial killer Israel Keyes admitted he enjoyed killing people, but couldn't or wouldn't give investigators a more meaningful answer when quizzed why he did it.

"There were just times, a couple of times, where we would try to get a why," said Anchorage Police officer Jeff Bell, who helped interrogate Keyes for hours.

"He would have this term, he would say, 'A lot of people ask why, and I would be, like, why not?'" Bell said.

Keyes confessed to killing eight people across the United States, but alluded to additional murders, FBI Special Agent Jolene Goeden and Bell told The Associated Press.

"Based on some of the things he told us, and some of the conversations we had with him, we believe the number is less than 12," Goeden said. "We don't know for sure. He's the only one who could have ultimately answered that."

They may never know the true number.

Keyes slit his wrist and strangled himself with bedding Sunday at the Anchorage Correctional Facility. He was facing a March trial on federal murder charges in the kidnapping and death of an 18-year-old Samantha Koenig, who was abducted from an Anchorage coffee stand Feb. 1.

He also wasn't going to stop. Authorities said he had weapons caches or body disposal kits stashed across the country.

One such disposal kit was found north of Anchorage. It included a shovel, plastic bags and bottles of Drano, which he told authorities would speed the decomposition of bodies.

A murder kit found in upstate New York had weapon parts, a silencer, ligatures, ammunition and garbage bags.

Keyes said other murder kits are hidden in Washington state, Wyoming, Texas and, investigators believe, somewhere in the Southwest, possibly Arizona.

Goeden and Bell conducted up to 40 hours of interviews with Keyes after his March arrest in Texas. During that time, Keyes confessed to killing Koenig, along with Bill and Lorraine Currier in Vermont, and five other people — although details for those victims were scarce.

The interviews also revealed Keyes' motivation, which was simple, Goeden and Bell said.

"He enjoyed it. He liked what he was doing," Goeden said. "He talked about getting a rush out of it, the adrenalin, the excitement out of it."

Keyes also liked seeing coverage of his crimes in the media, and he appeared to get a thrill out of talking about some of them with investigators, Goeden and Bell said.

His crimes started small with burglaries and thefts — until the urge escalated to murder.

Bell said Keyes told investigators the first violent crime he committed was a sexual assault in Oregon, in which he let the victim go.

"He planned on killing her but didn't," Bell said.

Keyes said the rape occurred sometime between 1996 and 1998 along the Deshutes River near Maupin, Ore., after he got the girl away from her friends. The girl was between the ages of 14 and 18, and would be in her late 20s or 30s now. No police reports were filed, and the FBI is seeking more information on the crime.

Of the five other murders Keyes confessed to, four were in Washington state and one occurred on the East Coast, with the body disposed of in New York.

In the case of the Curriers, authorities say Keyes flew from Alaska to Chicago on June 2, 2011, rented a car and drove almost 1,000 miles to Essex, Vt.

There, he carried out a "blitz" style attack on the Curriers' home, bound the couple and took them to an abandoned house. Bill Currier was shot, and his wife was sexually assaulted and strangled.

Keyes immediately returned to Alaska, and followed the case on his computer by monitoring Vermont media. The couple's bodies were never found after the house was demolished and taken to a landfill.

Leaving the area shortly after a murder was a familiar tactic for Keyes. After he abducted Koenig, he took her to a shed at his Anchorage home, sexually assaulted her and strangled her.

Keyes then left the next day for a two-week cruise, storing Koenig's body in the shed. Upon his return, he dismembered the body and disposed of it in a lake north of Anchorage. He was later arrested in Texas after using Koenig's debit card.

Koenig was his only known victim in Alaska. Goeden and Bell said he never explained why his broke his own rule of never killing anyone in the town where he lived because it's easier to be connected to such a killing.

The only mistake Keyes said he made was letting his rental car be photographed by an ATM when withdrawing money in Texas.

Unlike his earlier killings, the deaths of the Curriers and Koenig received a lot of news coverage.

"He was feeding off the media attention in the end," Bell said.

That wasn't the only change. His time between murders was growing shorter.

"He talked about that time period in between crimes, that over the last few years, that became quicker," Goeden said.

During their interviews, Keyes was willing to talk about the Koenig and Currier killings since he knew authorities had evidence against him.

"It was chilling to listen to him. He was clearly reliving it to a degree, and I think he enjoyed talking about it," Bell said of the Koenig and Currier deaths. But in the other cases, Keyes wasn't as forthcoming because he knew investigators had little on them.

Keyes, a construction contractor, told investigators that they knew him better than anyone, and that this was the first time he'd ever spoken about what he called his double life.

"A couple of times, he would kind of chuckle, tell us how weird it was to be talking about this," Bell said.

Even though he was talking to investigators, Keyes didn't want his name made public in any of the other investigations, especially the Curriers, because of the fallout of publicity. He threatened to withhold information if his name got out.

"If there was nobody else that he was concerned about, I think he wanted his story out there. He wanted people to know what he did," Goeden said. "What he was worried about is the impact that was going to have on the people that cared about him and were close to him."

Keyes will be buried Sunday in Washington state. 

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ANCHORAGE, Alaska — A security video showing the abduction of an Alaska barista is unnerving on its own, but it only hints at the horror ahead for the 18-year-old woman.

Samantha Koenig would soon be sexually assaulted and strangled after she was kidnapped from an Anchorage coffee stand, her body left in a shed for two weeks while her killer went on a cruise. After he returned, Israel Keyes photographed Koenig for a ransom note and then dismembered her body.

Those details were released by the FBI on Tuesday, two days after Keyes was found dead in his Anchorage jail cell in an apparent suicide. It's the most comprehensive account yet of a crime at the hands of a man who confessed to the slaying and told authorities he killed at least seven other people across the country over the past decade.

Serial killer found dead in Alaska jail cell, officials say

"These details are being provided both to fully explain the courage and resolve Samantha displayed in the final hours of her life, as well as in the hopes that the release of additional details will help investigations of other murders committed by Israel Keyes," the FBI said in a statement.

Once home from his trip, Keyes posed Koenig's body to make it appear she was still alive and took a Polaroid photo of her tied up, along with a newspaper dated Feb. 13 — 12 days after the abduction from a coffee stand, according to the FBI. Keyes later typed a ransom note demanding $30,000 from Koenig's family on the back of a photocopy of the photo and sent a text message to the woman's boyfriend on her cellphone with directions where he'd left the note at a local dog park.

Keyes dismembered Koenig's body and disposed of the remains in a frozen lake north of Anchorage after he cut a hole in the ice with a chain saw, authorities said.

Mark Thiessen / AP

During a news conference, police show surveillance video of Samantha Koenig, 18, making a cup of Americano coffee for a customer who shortly after abducted her Feb. 1, 2012, in Anchorage, Alaska. Police on Tuesday released the surveillance camera footage from the February abduction at the Common Grounds espresso stand in Anchorage.

Keyes, 34, was arrested in March in Texas, after using Koenig's stolen debit card at ATMs there and in Alaska, Arizona and New Mexico. He was facing a March trial in Koenig's death.

After his arrest, Keyes confessed to killing Koenig and at least seven other people. His other known victims were Bill and Lorraine Currier of Essex, Vt., who disappeared in June 2011. Keyes told authorities he also sexually assaulted and strangled Lorraine Currier.

Father of abducted barista, 18, pleads for her return

The couple's bodies have not been found.

Keyes did not identify the other victims or say where their remains were, other than that four were killed in Washington state and one was killed on the East Coast with the body disposed of in New York. Keyes had lived in Washington state and had property in upstate New York.

He told one of the lead FBI investigators in the case that his first victim was a teenage girl in Oregon that he sexually assaulted but did not kill, the Anchorage Daily News reported. FBI special agent Jolene Goeden told the newspaper that Keyes admitted that he was a teen at the time and that "he had the intention, he said, of killing her but but did not. And he did let her go."

Surveillance video
Also Tuesday, authorities released video footage of Keyes abducting Koenig, caught by a surveillance camera. Another video sequence shows him returning for Koenig's cellphone late that night, leaving Koenig bound in his truck, followed four minutes later by a man identified by the FBI as Koenig's boyfriend, who was looking for her. Keyes would use the cellphone to send text messages to the boyfriend and coffee stand owner that purported to be from Koenig saying she had a bad day and was leaving town for the weekend.

In the first video sequence, Keyes walks up to the small coffee stand and orders an Americano coffee, which Koenig makes. He then pulls out a gun and Koenig is then seen putting her hands up several times. At some point, Keyes makes her turn off the light. The light switch was close to a panic button, but Koenig never pushed it, probably because she was too afraid, police said.

Keyes then climbs into the kiosk and, police said, used zip ties to bind Koenig's hands behind her back before leading her out. He told Koenig he would let her go if her family paid a ransom, but that was never his intention, police said.

Body in icy lake is missing Alaska barista, police say

"He knew all along he was going to kill her," Anchorage homicide Detective Monique Doll said.

Police said Keyes removed the battery from Koenig's cellphone to avoid being tracked.

Koenig's body was recovered from the lake in April after Keyes told authorities of its location.

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Updated at 11:35 p.m. ET: Authorities are searching for a possible serial killer who has gunned down three Brooklyn business owners since the summer -- police believe the victims could have been targeted because they were Middle Eastern.

Detectives who specialize in hate crimes and FBI analysts who specialize in behavioral analysis have joined the case, authorities said.

Police Commissioner Ray Kelly said Monday that police are trying to identify a tall, balding man with a mustache who was seen on surveillance video carrying a black duffel bag near the scene of the latest shooting. NBC 4 New York has learned the same man was also seen on video near the second shooting in August.

Read more at NBCNewYork.com

Authorities say two other possible witnesses seen on video have been questioned and released.

The latest victim, 78-year-old Rahmatollah Vahidipour, a Jewish man from Iran, was killed Friday in his women's clothing boutique on Flatbush Avenue.

"The possibility of a bias motive here is something that can't be excluded," Kelly said.

After the latest killing, detectives discovered the same gun was used in the fatal shootings of two other shopkeepers when ballistics matched the .22-caliber gun shell casings on all three.

On July 6, Mohamed Gebeli, 65, an Egyptian immigrant and a Muslim, was found shot in the back of his shop, Valentino Fashion Inc. On Aug. 6, Isaac Kadare, 59, also Egyptian but Jewish, was shot in the head in his store, Amazing 99 Cent Deal.

There were other similarities, authorities said: The bodies were all partially obscured by clothing or, in one case, a box. The shops all lacked surveillance cameras, and the owners were alone in the store. The locations of the shops are each about four miles apart, with addresses that contain the number eight. Money was taken from everyone but Vahidipour, who had $171 in his pocket.

"We're trying to put it together. We're talking to the FBI; we're doing an all-out effort to solve these murders," Kelly said.

Kelly said it's reasonable to think the shooter had canvassed the area to find locations where no cameras existed.

"Here you have three stores where the proprietor is there by himself, no cameras in any of these," he said. "You'd have to speculate that some sort of reconnaissance was going on before the murders took place."

Kelly said they would like the tall man to come forward and identify himself. The commissioner said no one has been named a suspect and no arrests had been made.

The killings chilled local shopkeepers.

"Pretty nerve-wracking that a serial killer is on the loose in Brooklyn. You know it's the third one with the same gun," said Howard Prince, the manager of a business near the She She Boutique. Prince said police were stressing that no one should work alone.

"I mean that's not the part that concerns me," Prince said. "The part that concerns me is you take somebody's life that's 78 years old for no reason."

Kelly said city shop owners should be alert and aware of their surroundings and should call police or 911 at the sign of trouble.

Michael Goulding / AP, file

Rodney Alcala, now 68, has been behind bars since his 1979 arrest in a California killing. He appeared on a 1978 episode of "The Dating Game," the innuendo-filled matchmaking show that was a hit in its era.

NEW YORK - A man already convicted and on California's death row for the decades-old murders of four women and a 12-year-old girl now faces charges in the slayings of two Manhattan women in the 1970s.

Rodney Alcala was scheduled for arraignment Thursday for the deaths of Trans World Airlines flight attendant Cornelia Crilley and aspiring researcher Ellen Hover, both 23.

It was unclear who would represent Alcala or even whether he would have a lawyer. A former photographer with an IQ said to top 160, Alcala represented himself at his California trial that ended with his convictions in 2010 for the five murders. He is appealing.

Decades of suspicion, an indictment last year and 18 months of legal maneuvering over extraditing him culminated Wednesday with his arrival in New York City on a U.S. Marshals Service plane. He was placed in police custody.

'One brick at a time'
Alcala was indicted only recently, after the Manhattan district attorney's cold-case unit re-examined the cases, looked at evidence that emerged during the California trial and conducted new interviews with more than 100 witnesses.

California authorities had said they were exploring whether Alcala could be tied to cases in New York and other states, and they had released more than 100 photos, found in his storage locker, of young women and girls.

"These cases were built one brick at a time, as each new lead brought us closer to where we are today," District Attorney Cyrus R. Vance Jr. said when Alcala was indicted, adding that he hoped the indictment "brings a small measure of peace to the families and friends who have spent decades searching for answers, and justice."

Crilley was found, strangled with a stocking, in her Manhattan apartment in 1971. Hover was living in Manhattan when she vanished in 1977. Her remains were found the next year in the woods on a suburban estate.

Hover had a degree in biology and was seeking a job as a researcher, a private investigator for her family said at the time. A talented pianist, Hover was "enamored of the counterculture of the 1960s," cousin Sheila Weller wrote in a 2010 Marie Claire magazine piece about Hover's death. Weller has said she's gratified by his indictment in her cousin's death; she declined Wednesday to elaborate.

Hover's father, comedy writer Herman Hover, had been an owner of the one-time Hollywood hotspot Ciro's.

Her disappearance and Crilley's death made headlines and spurred extensive searches. TWA offered a $5,000 reward for information about Crilley's killing. Hover's relatives papered walls and kiosks with posters.

Lunch date
A note in Hover's calendar for the day she vanished showed she planned to have lunch with a photographer she had recently met, according to the family's private detective and news reports at the time. Her lunch date's name, authorities later said, was an alias that Alcala used.

Alcala had been eyed in Crilley's death for at least several years. New York Police Department detectives investigating her killing went to California in 2003 with a warrant to interview Alcala and get a dental impression from him.

A forensic dentist later found that a bite mark on Crilley's body was consistent with Alcala's impression, a law enforcement official has said. The official was not authorized to speak publicly and spoke on condition of anonymity.

Alcala, now 68, has been behind bars since his 1979 arrest in one of the California killings. Before that arrest, he also served a prison sentence on convictions of furnishing marijuana to a minor and kidnapping and trying to kill an 8-year-old girl.

He also had attended college and worked briefly as a typist at The Los Angeles Times, according to a 1979 story in the newspaper.

And he had made his way onto a 1978 episode of "The Dating Game," the innuendo-filled matchmaking show that was a hit in its era.

Introduced as a photographer with a yen for motorcycling and skydiving, the long-haired, leisure-suited Alcala won the contest. But the woman who chose him over two other contestants ultimately didn't go on a date with him, according to news reports.

His conviction last year came after a series of trials, overturned convictions and strange courtroom moments. Acting as his own lawyer, Alcala offered a rambling defense that included questioning the mother of one of his victims, showing a clip of his appearance on "The Dating Game" and playing Arlo Guthrie's 1967 song "Alice's Restaurant."

Alcala fought his extradition to New York, saying he needed to stay in California to attend court hearings and do other preparatory work on his appeal. The California Supreme Court rejected his argument last month.

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AP

An Illinois sheriff wants to dig up a backyard where serial killer John Wayne Gacy was once spotted at dawn, shovel in hand. Gacy, convicted of 33 murders, was executed in 1994.

An Illinois sheriff hopes to excavate a Cook County backyard in hopes of finding more victims of serial killer John Wayne Gacy, the Chicago Tribune reported. Gacy, convicted of killing 33 boys and young men and then stuffing them in the crawl space beneath his house, was executed in 1994.

But Anita Alvarez, the state’s attorney for Cook County, has so far denied Sheriff Tom Dart’s request, saying the sheriff does not have enough new information to merit a warrant.

The yard was dug up in 1998 after a retired homicide detective tipped off authorities that he had seen Gacy there one early morning in the 1970s, shovel in hand, the Tribune reported. They chatted briefly, and the detective went on his way. That dig produced a glass marble and flattened sauce pan.

Dart started looking into Gacy last year. He also wants to excavate Gacy’s mother’s yard, and the yard where Gacy once worked as a maintenance man, the Tribune reported.

Last year, his office exhumed bodies of victims and identified one, William George Bundy, who went missing at age 17, the Tribune reported.   

Gacy reentered the news again in February, when friends of a Gacy victim announced they believe that he had an accomplice in the murder of their roommate, John Mowery, a 19-year-old former Marine who disappeared on the night of Sept. 25, 1977.

Witnesses suggest John Wayne Gacy had an accomplice

Attorney Robert Stephenson told msnbc.com that he conclusively believes that “this individual was involved as an accomplice at least in this one (murder) and we suspect others as well.”

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AP

John Wayne Gacy was convicted of murdering 33 young men between 1972 and 1978.

Three people have come forward with new information that suggests serial killer John Wayne Gacy had an accomplice in some of his grisly rape and torture murders, two Chicago lawyers say.

The three were friends of one of Gacy’s 33 victims, John Mowery, and their stories indicate Mowery’s roommate had a hand in his death, criminal defense attorneys Robert Stephenson and Steven Becker say.

“We conclusively believe this individual was involved as an accomplice at least in this one (murder), and we suspect others as well,” Stephenson told msnbc.com on Friday.

Mowery, a 19-year-old former Marine, disappeared the night of Sept. 25, 1977. He was last seen alive leaving his mother’s house in Chicago after dinner. His body was among 29 corpses of young men and boys found buried on Gacy’s property in an unincorporated part of Norwood Park Township, a little over a dozen miles outside Chicago, in 1978. Four other victims were dumped in a river.

Becker and Stephenson said they recently spoke with two women and a man who knew Mowery. According to their accounts, a man who knew Gacy moved into Mowery’s Chicago apartment three days before Mowery went missing.

The day after Mowery disappeared, the two women went to his apartment looking for him. While there, they say, the roommate told them he knew of a location in the Chicago area where dead bodies were stored.

“He told us that he knew of a location where there were a bunch of dead bodies that nobody knew about, not even the police, which I remember very clearly because he said this with such a terrible smirk on his face,” one of the women told WGN.  (The women also spoke to the Chicago Sun-Times. Neither WGN nor the Sun-Times used their names because the women said they still fear the roommate.)

The roommate also reportedly said Mowery probably just took off on a trip and tried to persuade one of the women to take Mowery’s dog.

“If John was simply on his trip, there would be no need to give John’s dog away and seems to imply that Accomplice knew John was not coming back,” Stephenson and Becker conclude in a written summary.

They also said it’s unlikely that Gacy had enough time to kill Mowery and bury the body alone, and then show up for work at 6 o’clock the next morning at his contractor’s job in Michigan.

Mowery’s roommate would later testify as a prosecution witness at Gacy’s trial. He told the court he helped dig a trench in the crawlspace of Gacy’s home where most of the victims were found. But he denied knowing about any of the murders.

Stephenson and Becker say the roommate also matches the description of a second attacker that a man who survived a March 1978 sexual attack in Gacy’s home gave to authorities.

Related: Serial killer John Wayne Gacy had accomplices, lawyers say

Msnbc.com is not naming the former roommate because he has not been charged in the Gacy case. Stephenson and Becker said the man is apparently still living in the Chicago area. A message msnbc.com left at the telephone number the lawyers provided for the man was not returned.

Court records provided by Stephenson and Becker indicate the man served prison time in 2003 on a state aggravated battery charge for attacking a man with a bat. He was also among nine people indicted by a federal grand jury in November 2003 in an alleged conspiracy to burn down movie theaters in retaliation for labor contract disputes. He served 31 months in prison for that crime, according to Stephenson.

Stephenson and Becker have been pursuing new leads in the Gacy case on their own time for several months. They say the evidence they’ve uncovered suggests the so-called “Killer Clown” had help carrying out some of the murders.

The Cook County Sheriff’s Office has said it will review the lawyers’ findings and pursue investigations as warranted.

"Have we ruled out that someone would have helped Gacy in one or more of the murders? No," Cook County Sheriff Thomas Dart told msnbc.com last week.

Stephenson and Becker say the women in the Mowery case contacted Chicago police at the time about their encounter with the roommate but their information was never followed up on or forwarded to prosecutors working on the Gacy case.

“Had they known this accomplice moved in with John Mowery three days before he disappeared I think that would have changed the nature of this investigation,” Stephenson said. “This guy was an accomplice. There’s no other way to explain the connections."

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1978 photo of serial killer John Wayne Gacy.

Nearly two decades after Chicago serial killer John Wayne Gacy was executed for torturing, raping and murdering 33 men and boys in the 1970s, two lawyers say they’ve unearthed evidence that indicates he didn’t act alone in some of the slayings.

Criminal defense attorneys Robert Stephenson and Steven Becker, who are partners in a Chicago law practice, said they re-examined the circumstances surrounding the disappearances of some of the victims. Their conclusion: the so-called “Killer Clown” had at least three accomplices.

The Chicago Sun-Times and WGN-TV first reported on the lawyers’ claims on Thursday and Friday.

“There is significant evidence out there that suggests that not only did John Wayne Gacy not operate alone, he may not have been involved in some of the murders, and the fact that he was largely a copycat killer,” Stephenson told WGN.

Stephenson and Becker on Friday presented their findings to Cook County Sheriff Thomas Dart plus a lead investigator and a former prosecutor in the decades-old case.

Dart described the meeting as "very fruitful."

"They raised valid questions," Dart told msnbc.com in a telephone interview. "I definitely would not dismiss what they have said. It’s not out of left field. Its' well thought out."

The sheriff said investigators will follow up on the information and, if it proves solid, will try to locate the potential accomplices -- two of whom are believed to be still alive. The case has had so many twists and loose ends – seven Gacy victims remain unidentified, for example – that Dart is keeping an open mind.

"Have we ruled out that someone would have helped Gacy in one or more of the murders? No," the sheriff said.

Stephenson said he and Becker started looking into the Gacy case last year at the request of a mother who questioned the finding that her son, Michael Marino, was one of the bodies found on Gacy's property. A dentist who made the original body IDs re-examined X-rays and said he’s certain the victim was Marino, according to the Sun-Times.

The investigation into Marino's death led the lawyers to a flurry of leads and new information from other sources.

Stephenson estimates he and his law partner have voluntarily spent up to 30 percent of their work time over last six to eight months on the case -- without compensation.

“It’s one of those things, when you start meeting with family members and you start talking to them, knowing how important it is to them to have their questions resolved, you just feel compelled to do it,” Stephenson told msnbc.com on Friday.

"We've turned what we’ve had to the proper authorities. I’m sure they will take their time and look at it and do what is appropriate," he added.

Stephenson and Becker told the Sun-Times they found anomalies in the cases of victims Russell Nelson of Minneapolis and Robert Gilroy and John Mowery of Chicago. The three young men disappeared in 1977 and were among 29 victims found buried on Gacy’s property – most in the crawlspace of his home - in unincorporated Norwood Park Township outside Chicago in 1978. The remains of four other victims were dumped in a nearby river.

Gacy, a building contractor who performed as an amateur clown at fundraising events and children’s parties, was tried in Chicago in 1980 and convicted of 33 murders. He was executed in 1994.

Did Gacy have help?
Stephenson and Becker say a review of Gacy’s travel and work records and other court documents indicates he was out of town when Nelson and Gilroy disappeared.

Gilroy vanished on Sept. 15, 1977, between 5 p.m., when he talked to his girlfriend by telephone, and 6 p.m., when he failed to show up at a bus stop for a trip to an equestrian-riding class, the lawyers told the Sun-Times and WGN. But a copy of a plane ticket shows Gacy flew to Pittsburgh on Sept. 12 and didn’t return to Chicago until the night of Sept. 16, the lawyers say.

Nelson went missing on Oct. 19, 1977. A friend told police Nelson vanished that evening while they were outside a disco bar in Chicago. But Nelson’s mother said the friend later gave her a different account and also repeatedly asked her for money to help find him.

Stephenson told the Sun-Times he doesn’t believe Gacy could have snatched the 21-year-old Nelson from the street without the friend seeing anything.

A few months before Nelson disappeared, Gacy did some work at a drug store just blocks from where Nelson’s friend lived, Becker and Stephenson said. And Nelson’s mother said the friend offered Nelson’s two brothers a job with Gacy.

Some have speculated the friend, who according to the lawyers is still alive and living in another state, may have been involved in Nelson’s disappearance.

“I don’t know that [the friend] was involved,” Stephenson told the Sun-Times. “But I know that he wasn’t telling the truth here.”

“I think it tells us that John Wayne Gacy was using other individuals to procure young boys over state lines,” Becker told WGN.

Mowery, 19, was last seen alive at 10 p.m. on Sept. 25, 1977, leaving his mother’s house after dinner. He was scheduled to work the next morning, Stephenson told the Sun-Times.

Contractor records show Gacy was at a job in Michigan at 6 a.m. on Sept. 26, 1977, and was in Michigan until Sept. 30, 1977, Stephenson said.

Stephenson told the newspaper he doubts Gacy would have the time to abduct, torture and kill Mowery in the narrow time frame between Mowery’s disappearance and Gacy heading to work in Michigan.

Stephenson said other evidence suggests Gacy had accomplices, too.

Gacy was known for using a rope and board to strangle his victims, but autopsies on Gilroy and Nelson showed they died from asphyxiation due to suffocation rather than strangulation, WGN reported.

And, according to the Sun-Times:

After he was arrested in 1978, Gacy told officers: “Who else do you have in the station? There are others involved.” He was asked, “Directly or indirectly?” and responded, “Directly. They participated.” He was asked, “Who are they?” and responded, “My associates.”

Also, Gacy told police he got the idea of putting his victims on a “torture board” from Elmer Wayne Henley, a Texas serial killer. Henley was an accomplice of Dean Corll, who killed at least 28 boys and young men. Henley killed Corll and is now serving a life sentence.

“Gacy was a copycat,” Stephenson told the newspaper. “And he was copycatting a killer who used accomplices.”

Stephenson told msnbc.com: "I think I can say, from our information to this point, we believe there are at least three accomplices."

One of them was the "friend" of Nelson; Stephenson wouldn't say who the other two were.

Sheriff Dart, who also declined to release the names, said one of the possible accomplices is believed to be dead. He said investigators will interview the other two if follow-up work indicates they could have been involved in some of the Gacy killings.

"There have been countless leads that have come in -- some of them obviously not valid from the get-go, others ones much more so. So here we have leads that are valid to be run out. This would be in a much higher category of leads," he said of the lawyers' information.

Loose ends

Terry Sullivan, who was on the Gacy prosecution team as a state’s attorney and who wrote a book, “Killer Clown: The John Wayne Gacy Murders,” about the case, says he wouldn’t be surprised if it turns out Gacy had help in committing his crimes.

“I felt from the beginning that there may be loose ends. It was such a huge case, especially at the time,” Sullivan told WGN.

But Gacy’s defense lawyer, Sam Amirante, doesn’t buy the accomplice theory.

“Nothing as far as killing or recruiting … we thought about it, but we just never saw any evidence,” he told WGN.

Amirante said Gacy confessed to everything early on, and only after years in prison did he begin to change his story.

That's a point a former prosecutor on the case also raised, Dart said: "Gacy was trying everything he could to avoid being executed. If there was an accomplice or accomplices …he would have brought it out at that point to save his own skin.”

Stephenson contends Gacy did claim to have accomplices shortly after his arrest.

All parties agree the Gacy case has been anything from ordinary.

Dart estimates it'll take a month or two to fully investigate the new information.

As for victims' families, the reaction has been mixed.

"We've been in contact with many, many victims' family members over the past six months. None of them were really surprised by what was announced last night," Stephenson told msnbc.com. "Some of them don’t want to talk about it and revisit old wounds. Others do, and those that do have provided really valuable information."

Meanwhile, seven victims of Gacy remain unnamed. In December, the Cook County sheriff’s office announced that it had identified, through DNA testing, an eighth previously unidentified victim: 19-year-old William Bundy, a Chicago resident who disappeared in 1976. The sheriff also told four families that DNA tests ruled out their missing relatives as among Gacy's victims.

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