TODAY's Ann Curry talks with Susan Powell's parents, Chuck and Judy Cox, who say that they feared for the lives of their grandkids and believed that Josh Powell would do something drastic "if he felt cornered."
Before setting his house ablaze and killing himself and his two young sons, Josh Powell left a voicemail for family members saying he couldn't live without the boys and didn't want to go on anymore.
ABC News obtained what it says was a voicemail Powell left for his family members. In the recording played Tuesday on "Good Morning America," Powell also said he was calling to say goodbye and apologize.
“Hello, this is Josh. And I’m calling to say goodbye,” a shaking voice on the voicemail said. "I am not able to live without my sons, and I'm not able to go on anymore. I'm sorry to everyone I've hurt. Goodbye.”
The message was left 20 minutes before Powell killed himself and his boys, ABC reported.
But the double murder-suicide appeared to be in the works for longer than just those 20 minutes. In the days leading up to the fire, Powell had been donating his sons' books and toys, according to ABC.
The investigation and autopsy reports released late Monday show the acts of a violent man who meticulously planned his actions, culminating Sunday in Powell setting his house ablaze and taking a hatchet to his children's necks.
As authorities work to determine exactly why Powell committed the murders, investigators said they're no closer to answering the question they've had for two years.
"We still haven't identified or found where Susan Powell is," said West Valley, Utah, Police Chief Buzz Nielsen, who is in charge of the investigation into the young mother's disappearance.
For now, even with the longtime "person of interest" in the probe dead, police say the case remains open, though some mysteries may never be solved.
Just days before the horrific murder-suicide, in a motion seeking custody of his children filed with a Washington state court, Powell said he missed his wife, and would remain strong for the boys.
The sons of missing mom Susan Powell suffered neck and head injuries at the hands of their father, Josh Powell, before dying in the house he set on fire. NBC's Miguel Almaguer reports.
"A lesser person would fall under the intense scrutiny I am facing, but apparently my inherent resilience as a person makes it increasingly difficult for them to pursue their agendas," Powell wrote. "I am standing tall for my sons, but it deeply hurts to face such ridicule and abuse.
"I know my own heart is free of any guilt regardless of what people claim," he added.
Things changed dramatically when the judge ruled against him, ordering the children to remain with Susan Powell's parents for now.
On Sunday, Powell's boys came for a routine supervised visit. They ran ahead, the social worker falling behind. Powell then locked the door, used a hatchet on his kids, and lit the house on fire.
Ultimately, Powell and both boys died of smoke inhalation, Pierce County Medical Examiner's Office investigator Melissa Baker said Monday evening.
But they also suffered "chop injuries" that contributed to their deaths — 7-year-old Charles was struck on his neck and 5-year-old Braden had injuries to both his head and neck, Baker said.
Pierce County Sheriff's Detective Ed Troyer said investigators found a hatchet that they believe was used on the boys.
"We recovered a hatchet — a small ax," he said. "It was right there with" the bodies.
Authorities also said Powell had made thorough plans well ahead of the murders.
"This was definitely a deliberate, planned-out event," Troyer said.
Powell had painted himself as a tortured man, ridiculed without reason in the disappearance of his wife, steadfastly insisting he was innocent until the end, authorities and family members said.
Susan Powell's parents, the boys' grandparents, had had custody of the kids before their death. They told NBC's TODAY Show on Tuesday that Powell felt "cornered."
"We felt [the boys] were safe as long as they were with us, but we were concerned about the visitation," Chuck Cox told NBC's Ann Curry. "We knew if he was cornered and felt like there was no way out, he was capable of this. We had made that known to police and all the law enforcement involved. They were aware of our concerns."
Added Judy Cox, "He didn't like us and he just wanted to get the kids away from us so much. And it really bothered him that the boys were showing so much affection to Chuck."
Authorities recovered two 5-gallon cans of gasoline inside the rented Washington home. Gasoline from one 5-gallon can was spread throughout the house and used as an accelerant in the huge blaze. The other can was found by the three bodies, Troyer said.
He said minutes before the fire, Powell sent emails to several people, including his lawyer, saying, "I'm sorry. Goodbye." To others, including his cousins and pastor, he sent longer emails, with instructions on where to find his money and how to shut off his utilities. In at least one email, he wrote that he couldn't live without his boys, Troyer said.
But, he said, "There's no indication about Susan in anything that we've found so far."
Nielsen said detectives want to question Powell's father, Steve Powell, about Susan's disappearance. He described Steve Powell as another "person of interest" but noted the elder Powell is "not in our sights" in terms of any potentially imminent arrest.
Steve Powell has been in jail on voyeurism and child porn charges since last fall after authorities found explicit images on his computers during a search of his home in the case of his missing daughter-in-law.
After his arrest, the state turned the boys over to Chuck and Judy Cox.
Steve Powell claimed on national television last year to have had a flirtatious or even sexual relationship with Susan — something her family has adamantly denied.
Josh Powell's account of the night his wife disappeared
Josh Powell claimed that the night his wife vanished in December 2009, he took the boys from their West Valley City home, about 10 miles outside Salt Lake City, on a midnight camping trip in freezing temperatures — a story her parents never believed. Authorities searched the area in the central Utah desert but came up empty.
Less than a month after the disappearance, Josh Powell moved the boys to his father's home in Puyallup, south of Seattle.
Sunday's tragedy left the Coxes devastated. They spoke to reporters Monday to give a glimpse of the lives the boys led.
They said the boys played happily and didn't want to visit their father when the time came for their weekly Sunday visit.
“They were having a good time and didn’t want to stop and see daddy,” Chuck Cox told KIRO TV in Seattle. “They seemed to be losing interest in going to see him. They liked it here.”
But Judy Cox said she talked them into going — and she now regrets it.
Chuck Cox said he didn't necessarily think there was any more the court could have done legally to protect his grandchildren. However, he said he didn't like that there was only one supervisor during their visits with their father.
"We suspected that if he had the boys in his control, with him, and he felt the police were closing in, he was capable (of hurting them)," Cox said. "We didn't like that there was only one supervisor. Frankly, she couldn't have stopped him if he wanted to do something."
The boys were emotionally distant when they first arrived at their grandparents' home, Charles Cox said, but recently they had become warmer. And that gave the grandparents hope that maybe someday they would be able to relate what happened to their mother.
"They were like little robots. If you asked them about mommy, they would run away," he said. But "in the last week, I could not sit down without them climbing up on my lap."
Chuck Cox said that the summer after his daughter disappeared, Braden drew a picture at day care of a van with three people in it, and told caregivers who asked him about it that it was a picture of his family going camping: "Mommy's in the trunk," the boy reportedly said.
On Tuesday, the Coxes, showing little emotion as they spoke of their deceased daughter and grandkids, told The TODAY Show, their faith was helping them to get through this.
"We know where our daughter is. We know she is not here on this earth ... and that she is safe, and we know that the boys are now back with their mother, and that gives us a lot of strength."
Nielsen said Utah authorities would continue with their investigation, and hoped to make an arrest in the Susan Powell case this year.
"On a criminal case of this nature, you've got one shot. You've got to make sure everything is done right," Nielsen said. "Our case is not closed."
The Associated Press contributed to this report.
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