Josh Powell put some thought into killing his sons.
In the days leading up to Sunday, he gave away the toys and books he kept for the two boys at his Graham-area house and stopped somewhere to fill two 5-gallon cans with gasoline, authorities said Monday.
When Charlie, 7, and Braden, 5, arrived for a scheduled visit about noon, their father had either saturated his home with gasoline or was about to, Pierce County sheriffs spokesman Ed Troyer said. He also had a hatchet on hand he used to chop them in the head and neck.
Minutes before, hed sent out emails to friends, relatives and his pastor, saying good-bye and apprising them of where he kept his money and how to cancel the utilities.
One of the emails said, I cant live without my boys, Troyer said.
He was taking care of his final business, Troyer told news reporters from around the nation whod gathered outside the charred husk of Powells house. This is something he was intending on doing.
Then he did it, sparking an inferno that destroyed the house and killed, Charlie, Braden and himself.
Investigators found one of the gas cans near the bodies.
Teams of detectives were fanning out across Pierce County to try to piece together Powells movements in the last few days of his life, including where he got the gasoline, Troyer said.
Also Monday, detectives from West Valley City, Utah, arrived in Pierce County to learn what, if anything, Powells death means for their investigation into the disappearance of his wife, Susan Cox Powell.
The Medical Examiners Office also conducted autopsies on Powell and his sons. The boys cause of death was listed as carbon monoxide poisoning with chopping injuries as a secondary cause. The manner was listed as homicide.
Powell died of carbon monoxide poisoning, the medical examiners reported. The manner was listed as suicide.
Troyer said none of the emails Powell, 36, sent out Sunday mentioned his wife, Susan Cox Powell, who disappeared under mysterious circumstances from their Utah home in December 2009. She was 28 when she went missing.
Theres no indication about Susan in anything weve found so far, he said.
Sheriff Paul Pastor said detectives were trying to determine which of Joshs family members or friends might have received prior indication of the murders.
We may be looking at (search) warrants to look at all people who may have information, Pastor said. We want to know what they knew of and when they knew it.
Were not going to be able to find out why it happened. You cant crawl inside someones mind whos dead.
Authorities considered Powell a person of interest in his wifes disappearance from the beginning, but he was never arrested or charged with a crime.
West Valley City Police Chief Buzz Nielsen flew to Pierce County on Monday and addressed reporters near the crime scene.
He said Powell had no idea where West Valley City police were in their investigation in Susan Powells disappearance, so it was unlikely that triggered his Sunday actions.
Wherever we are in the criminal case, Josh didnt know about it, the chief said. He didnt talk to us. He didnt like us. This was a decision he made. It didnt have anything to do with what were doing.
Nielsen said he was optimistic his department could solve Susan Powells disappearance despite the death of her husband.
I promised (her parents) I wasnt giving up, and Im not, he said. We want to get some closure here.
Salt Lake County prosecutors are not ready to release the contents of search warrants served on the West Valley City home of Josh and Susan Powell. District Attorney Sim Gill said prosecutors met last month to review materials in the Powell case in conjunction with custody proceedings in Washington.
This continues to be a missing persons case with an open and active investigation, Gill said. Until I have some conversation with law enforcement (about whether) they will close their case out or not, its still a missing persons case.
Josh Powell and the boys moved from Utah to Puyallup not long after his wife disappeared. They stayed with Powells father, Steve, until September 2011, when he was arrested and charged with voyeurism and possessing child pornography.
The state then took Charlie and Braden into protective custody, ultimately placing them in the care of Susans parents, Chuck and Judy Cox, also of the Puyallup area.
As late as Wednesday, Josh Powell was fighting to regain custody, but Superior Court Judge Kathryn Nelson said she wouldnt consider returning his boys to him permanently until he underwent a psychosexual examination.
Nelson declined to comment on the case Monday, saying she is barred from speaking about it because more matters related to the case might come before her.
A social worker dropped Charlie and Braden off at Powells rental home in the 8100 block of 189th Street Court East on Sunday afternoon for a supervised visit with their father. Powell moved into the home in August, Troyer said.
The boys went inside and Powell shut the door on the social worker. She pounded on the doors and windows. She smelled gasoline, Troyer said.
Minutes later, the house exploded and was engulfed in flames.
The death of Charlie and Braden reverberated throughout Pierce County on Monday.
After sundown, dozens gathered for a vigil at Tacomas McKinley Park, where Charlie and Braden loved to frolic near the pond and hatch plans to catch and train squirrels.
Lynnette Scheidt organized the gathering and spoke briefly before leading the crowd in a rendition of Amazing Grace.
Everybodys grieving. These were two very small children, Scheidt said. We cant ask ourselves why, all we can do is try to make it better. Were here to offer hugs and support.
During the song, some placed Styrofoam cups containing votive candles into the water. Several swiped at tears streaming down their faces.
Jennifer Bleakley, who lives a block from Powell, stood with her two daughters grappling with how to forgive a man who could kill his children, a man she called a monster.
As hard as it seems, we need to forgive Josh, said a crying Bleakley. But those boys, they were taken from us too soon. Theyre in a good place now, with their mother.
Staff writers Stacey Mulick, Stacia Glenn and Debbie Cafazzo and The Salt Lake Tribune contributed to this report.