(CNN) — Shortly before he set fire to his Puyallup, Washington, house and killed himself and his two sons, Josh Powell — a suspect in the 2009 disappearance of his wife — apparently sent a three-word email to his attorney.
It said simply: “I’m sorry. Goodbye.”
It was a tragic end to a puzzling case that began two years earlier in West Valley City, Utah, with the disappearance of 28-year-old Susan Cox-Powell and devolved into a bitter custody dispute between Powell and his wife’s parents.
Pierce County sheriff’s spokesman Ed Troyer accused Powell of committing murder-suicide, saying Sunday’s fire “was done intentionally.”
“This was all on him,” Troyer said. “He set this up. He did it.”
The sheriff’s department has copies of the e-mail Powell sent to his attorney as well as family and friends that said “he couldn’t live with what was going on,” Troyer said.
While a medical examiner had yet to definitively identify the bodies, the sheriff’s spokesman said “we believe it is the three of them.”
“This was something that was done deliberately and intentionally, and the plan was carried out very quickly,” he said.
The events appeared to have been set in motion days earlier when a judge refused Powell’s petition to regain custody of his children and instead ordered he undergo a number of psychological evaluations — an order that came after authorities turned up child pornography in the home he shared with his father.
As part of the investigation into Cox-Powell’s disappearance, Utah authorities searched a Washington house where Powell, his two sons and his father, Steven Powell, were living last year.
During the search, investigators “discovered numerous images and recordings of adult and juvenile females,” according to a statement released by the Pierce County sheriff’s department.
Powell’s father, Steven, was subsequently charged with 14 counts of voyeurism and one count of possessing images of children engaged in sexually explicit conduct, according to court documents.
Following the arrest of Powell’s father, custody of his sons was given to his wife’s parents, Judith and Charles Cox, according to Washington state court records.
On Sunday, shortly after noon, Powell was standing outside his home in a quiet, tree-lined cul-de-sac waiting for a social worker to bring his two boys — 5-year-old Braden and 7-year-old Charlie — for a supervised visit, authorities said.
As the children got to the door, Powell pushed the social worker back, quickly brought the two boys inside and locked the door.
The social worker, who later reported smelling something similar to gas at the time, tried “pounding the doors, trying to get in,” said Gary Franz, a deputy chief with Graham Fire and Rescue.
About two minutes later, as she was calling her supervisor, the house exploded, Franz said.
The powerful explosion shook houses and rattled windows, with debris landing on lawns blocks away.
“All the walls in the house were on fire, almost immediately,” neighbor Ryan Mickle told CNN affiliate KIRO.
“I didn’t hear anybody inside.”
Jennifer Bleakley, who lived near the Powell home, was in the kitchen making coffee when the explosion violently rattled windows and doors in her home.
“It really hurts my heart. My heart ached for those boys anyway,” she told CNN affiliate KOMO, wiping away tears.
News of the explosion and deaths quickly made it to Utah, sending shock waves through the Powell-Cox family.
“I think this is his admission of guilt, and he just couldn’t handle it anymore,” Kirk Graves, Powell’s brother-in-law, told CNN affiliate KUTV.
Powell was the sole suspect, according to West Valley City Police Chief Buzz Nielsen, in the disappearance of his wife, who went missing on a cold December night in 2009.
“We always kept Josh as a target,” Nielsen told CNN affiliate KSTU.
According to investigators, Powell had said the last time he saw his wife was the night he and his two sons — then ages 2 and 4 — left to go camping.
Powell told authorities he left the house sometime after midnight in below-freezing weather for a desert area in Utah’s Tooele County.
Cox-Powell’s sister eventually reported her missing. A month later, Powell and his children moved from Utah to Washington.
As late as last month, Utah authorities were still working to connect Powell to the disappearance of his wife, who authorities believe is dead.
“We just needed a little bit more. Everywhere we looked, it always came back to Josh,” Nielsen said.
It was that belief that appears to have driven Powell to attempt to cast off suspicion in an affidavit filed as part of last week’s custody hearing.
“If anyone wants to be honest with themselves and the situation, the real story is not that anyone is a bad person, including me,” he said. “The story is one of overcoming and rising above what many people think are insurmountable challenges.”