Peter Haley / The News Tribune via AP
A Pierce County Sheriff's deputy and Graham Firefighters work around the smoldering remains of a house near Fredrickson, Wash., Feb. 5, where, according to a sheriff's spokesman, three bodies were were found. The bodies are believed to be Josh Powell and his two sons.
By msnbc.com staff and news services
Updated at 8:57 p.m. ET:
?GRAHAM, Wash. -- An explosion at the home of Josh Powell, the husband of a missing Utah woman, killed him and their two young sons shortly after the boys were brought to the house by a social worker for a supervised visit, officials said Sunday. A law enforcement official said the blast appeared to be intentional.
Powell let the boys in the house, then blocked the social worker from entering, said Graham Fire and Rescue Chief Gary Franz.
The social worker called her supervisors to report that she could smell gas, and the home exploded.
Sept. 29, 2011: Josh Powell could lose custody of his two sons.
Sgt. Ed Troyer, Pierce County sheriff's spokesman, said emails that Powell sent authorities seemed to confirm that Powell planned the deadly blast. Troyer didn't elaborate on the contents of the emails, but said they make police believe "this is intentional, this is planned."
A lawyer for Powell says he received a three-word email from his client just minutes before Powell and his two boys died in a house explosion. It said, "I'm sorry, goodbye."
Attorney Jeffrey Bassett told the Associated Press the email arrived at 12:05 p.m. Sunday, but he didn't see it until two hours later, when others informed him of the blast.
Authorities said they found three bodies in the home late Sunday afternoon as fire crews and police continued to search the rubble. Troyer said it appeared some sort of accelerant was used to make the house burn faster.
"Everything we know right now, this has become a crime scene," Franz said.
Powell was under investigation in the disappearance of his 28-year-old wife, Susan Powell, from their home in West Valley City, Utah, in December 2009. He claimed he had taken the boys on a midnight excursion in freezing temperatures when she vanished.
The case took a bizarre turn last year after Powell's father, Steven, was arrested for investigation of voyeurism and possessing child pornography. Josh Powell?was living at his father's home at the time, and a judge gave Susan Powell's parents custody of the boys, aged 5 and 7.
Ted S. Warren / AP file
Josh Powell leaves a courtroom on Sept. 28 in Tacoma, Wash., after a judge awarded temporary custody of Powell's two sons to Susan Powell's parents.
View images of the explosion at NBC affiliate King5.com
Last week, a judge ruled that the children of missing Utah mother Susan Powell must remain in the custody of her parents, and that they would remain with the grandparents unless their father agreed to undergo psycho-sexual evaluation.
Troyer said the elder Powell was put on suicide watch in custody after he was told of the deadly blast. "Steve Powell didn't seem very upset by the news, but was angry towards authorities who notified him," Troyer said.
Sherry Hill, a spokeswoman for the state Department of Social and Health Services, said the social worker who was with the children was not a Child Protective Services employee but a contract worker with a private agency that supervises visits for the state.
"The visit supervisor for this particular agency had taken the children to the home. When she does that, she sits through the visit and might take notes on her observations," Hill said. "She pulled up in the car, and the kids ran out ahead of her. He closed the door and locked it. She wasn't able to get in, and that's when she smelled gas."
"It's the most horrifying thing you can imagine happening," said lawyer Steve Downing, who represented Susan Powell's parents, Chuck and Judy Cox, in the custody fight. "The Coxes are absolutely devastated. They were always very fearful of him doing something like this, and he did it."
Bassett said he represented Powell free of charge because "every parent deserves the right to an attorney." Powell called or emailed him at least once a day, and often more than that, and in their conversations "he never once admitted doing anything regarding Susan. In fact, he denied it."
Sgt. Mike Powell of the West Valley City Police Department in Utah, which is handling the investigation into Susan Powell's disappearance, said it was too soon to say how Josh Powell's death may impact their probe.
"Quite frankly, this has obviously quickly unfolded up in Washington and we're obviously just working through the details ourselves here," Powell said Sunday.
"We are in contact with authorities," Powell added. "It's obviously an ongoing situation in Washington at this point."
Kirk Graves, 39, of West Jordan, Utah, Josh Powell's brother-in-law, said he and his wife, Jennifer, were stunned by the news. (Jennifer Powell Graves is Josh Powell's sister.)
"It's a shock. A total complete shock," he said. "We never contemplated the idea he would do something like this. You just don't expect it from a father."
Kirk Graves said he and his wife think Josh Powell deliberately set off the explosion to kill him and his sons.
"His world was falling apart around him and he was going to lose his boys and get arrested for Susan's disappearance," he said. "He's a narcissist and he has no love for anyone but himself.
The Associated Press and Reuters contributed?to this report.
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