PIERCE COUNTY, WA (CNN/ KING / KIRO / KSTU) – The case of a missing Utah woman took a tragic turn Sunday when Washington State authorities say they believe Josh Powell deliberately set off an explosion that took his life and the lives of his two boys.

Josh Powell was the focus of an investigation into the disappearance of his wife, Susan Cox-Powell. Deputies said it appears Powell sent an email that apologized and said goodbye shortly before the fire.

“This is all on him. He set this up. He did it. He is the one who started the fire,” said Ed Troyer, the Pierce County Sheriff’s office spokesman.

Investigators said a foster-care case worker brought Powell’s two boys to his home for a supervised visit. As the children got close to the door, Powell dragged them inside and locked the case worker out.

Moments later, a fiery blast leveled the house

The blast came just days after Powell was denied custody of his boys by a Washington judge, who ruled they should remain with their maternal grandparents.

Powell was a person of interest in the case of his missing wife who hasn’t been seen since Dec. 2009. A month after she vanished in Utah, Powell moved to Washington with his sons.

Utah police said they were building a case to charge Powell with murder.

Now family, friends and investigators must face the fact that some of the answers they wanted may have been lost in the flames.

Authorities are also investigating Josh Powell’s father for possession of child pornography and voyeurism.

Court documents say detectives found sexually-explicit images of juveniles on Stephen Powell’s computer last year, during their investigation into the Susan Cox-Powell disappearance.

The grandfather was living with his son and the boys at that time, but he is now in jail on those charges.;;playerWidth=300;playerHeight=240;isShowIcon=true;clipId=6711361;flvUri=;partnerclipid=;adTag=Station%252050;advertisingZone=;enableAds=true;landingPage=;islandingPageoverride=false;playerType=STANDARD_EMBEDDEDscript;controlsType=fixed

Article Courtesy of WOIO 19 Action News

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