Miami-Dade Police Dept. / AP

This undated booking mug made available by the Miami-Dade Police Dept., shows Rudy Eugene, 31, who was shot and killed by Miami-Dade Police after he refused to stop eating another man's face in Miami, Saturday, May 26, 2012. The victim remains hospitalized in critical condition.

The man who mauled off a homeless man's face over Memorial Day weekend apparently had no human flesh in his stomach, a report shows.

Law-enforcement sources told the Miami Herald an autopsy revealed 31-year-old Rudy Eugene had undigested pills in his stomach but no human flesh. The pills have not yet been identified.

Eugene was fatally shot by an officer after he refused to stop chewing on Ronald Poppo's face along the MacArthur Causeway.

Read the original story on NBCMiami.com

Though officials have speculated bath salts may have sparked Eugene's wild behavior, it remains unknown what prompted the attack.

Girlfriend of face-eating attacker blames drugs or voodoo

Officials told the Herald a preliminary review found marijuana in Eugene's system. Those who knew Eugene said he was known to smoke marijuana but the drug is not known to cause violent spurts.

A source also told the newspaper Eugene did not have his two front teeth but that chunks of flesh were found between his teeth. The source also said pieces of flesh were found on the floor of the scene.

What caused naked face-chewing attack: Bath salts, LSD?

Officials said the autopsy report would not be released to the public until the investigation into the shooting concludes - a process that could take more than a year.

Poppo, meanwhile, continues in critical condition in the hospital.

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The grisly Miami crime scene where police fatally shot a naked man chewing the face off his victim will soon be a tourist stop.

The Miami “Mystery & Mayhem: Crime Tour” tour given by Miami-Dade College professor Paul George, as part of HistoryMiami tours, will stop on the MacArthur Causeway, the South Florida Business Journal reported.

“Horrible as it was, it is part of our history,” George told the Business Journal. “Currently, our tour takes us over the causeway right past the site, so this fits well.”

George, a history professor at Miami Dade College, runs history tours that also include Al Capone's home and the cemetery where Julia Tuttle, a city founder whose name is on a causeway famed for sheltering homeless sex offenders, is buried, HistoryMiami says. The group did not say when the next crime tour will be.

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Miami attracts around 12.6 million overnight visitors a year, according to the Greater Miami Convention and Visitors Bureau.

Miami-Dade Police Dept. / AP

Rudy Eugene, 31, was shot by Miami-Dade Police after he refused to stop eating another man's face in Miami on May 26.

In Milwaukee, a tour highlighting the haunts of serial killer Jeffrey Dahmer sparked an uproar after Groupon offered discounted tickets to see where he stalked his victims, some of whom he mutilated and cannibalized. The chocolate factory worker was arrested in 1991 and beaten to death in prison in 1994.

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Despite protests by vicitms’ families, the Dahmer tours go on every Saturday, Amanda Morden of operator BAM Marketing and Media told msnbc.com.

“Interest in the tours has come from both national and international tourists as well as professors of history and psychology from universities across the United States,” Morden said.

Among other famed crime tours are the Jack the Ripper Tour in London, The Real Black Dahlia in Los Angeles, the Torso Murder Tour in Cleveland and the self-directed Gangster Walking Tour in St. Paul, Minn., along with mob tours in New York, Las Vegas and Sicily.

Related: After gory incidents, online 'zombie' talk grows

In Miami, an attacker identified as 31-year-old Rudy Eugene walked naked on the sidewalk near the causeway’s Biscayne Boulevard exit May 26 before he encountered his victim, Ronald Poppo, 65. Eugene appears in videos to struggle with Poppo, throwing him on the sidewalk as cars and bicyclists speed past and a Metromover public transit car passes by overhead. About 16 minutes into the attack, an officer appears and fires at Eugene, who police said first growled at the officer before continuing to chew Poppo’s face.

Poppo is reported to be in critical condition in a hospital.

Follow msnbc.com's Jim Gold on Facebook here. 

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Miami-Dade Police Dept. / AP

This photo from the Miami-Dade Police Department shows Rudy Eugene, 31, who was shot and killed by police.

The girlfriend of the face-eating attacker who mauled off most of another man’s face said her boyfriend was either unknowingly drugged or placed under a voodoo curse.

She told the Miami Herald the attacker, identified as 31-year-old Rudy Eugene, was “sweet and well-mannered.” The girlfriend, who asked that her name not be disclosed, said she was shocked to hear her boyfriend was the man everyone was calling the “Miami Zombie.”

“Something happened out of the ordinary that day. I don’t want him to be labeled the Miami Zombie,” she told the Herald. “He was a person. I don’t want him to go down like that.”

Read the original story at NBCMiami.com

Eugene was fatally shot by an officer as he chewed off more than 80 percent of a homeless man’s face. The victim, identified as 65-year-old Ronald Poppo, remains in critical condition at Jackson Memorial Hospital.

The Jackson Memorial Foundation said Thursday that it has set up a fund to help Poppo through its website, www.jmf.org.

Surveillance videos captured by security cameras at the Miami Herald building show Eugene walking on a pedestrian bridge near MacArthur Causeway Saturday and encountering his victim.

Handout / Reuters

Ronald Poppo, who was savagely mauled by another man, is seen in a photo released by the Miami-Dade Police Department.

In the nearly 20-minute attack, Eugene dragged Poppo along the sidewalk and ripped his clothes off, the video showed.

Authorities said when the officer, identified as Jose Rivera, arrived, he was forced to open fire and kill Eugene when he continued to savagely attack Poppo’s face. Officials said Eugene growled at the officer and kept eating at the man’s face.

Eugene’s girlfriend said she was hysterical when she heard it was her boyfriend who had attacked the man on MacArthur Causeway.

“I thought to myself, ‘Oh my God, that’s crazy,’ she told the Herald. “I didn’t know that it was Rudy.”

She said Eugene was never violent around her and though he smoked marijuana, didn’t use stronger drugs, the newspaper said.

Records showed Eugene was arrested for a variety of charges between 2004 and 2008, including battery and trespassing. He also served time for selling and possessing marijuana.

The girlfriend said the day he died Eugene kissed her goodbye, told her "I love you" and left early in the morning with his Bible in his hand.

She said Eugene, who worked at a car wash, would always read the Bible to her and carried it with him everywhere.

Eugene's brother told NBC 6 Wednesday that he was also a little shocked when he heard about what happened.

“Pretty uncharacteristic of him. It was real weird – kind of mixed emotions, I think,” said the brother, who only gave his first name, Thompson. “Through the whole thing I was mostly thinking about my mom.”

Eugene's girlfriend said though she’s never believed in voodoo, she does now.

“I don’t know how else to explain this,” she told the Herald.

The Jackson Memorial Foundation said those interested in contributing to Poppo's fund should click the "Take Action Now" tab on its site, then click donations, select "others" under contribution details, and type in Ronald Poppo.

Checks made out to Jackson Memorial Foundation can also be mailed to Jackson Memorial Foundation, Park Plaza East, Suite G, 901 NW 17th Street, Miami, FL 33136.

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