A tragic twist in the case of missing Utah mother Susan Powell -- her husband killed himself and their two young sons in an explosion on Sunday.
Susan Powell disappeared in 2009. Her body has never been found, and while he was never charged, police have called Josh Powell a "person of interest."
The couple's two sons have been in the custody of Susan Powell's parents. On Sunday a social worker brought the children to Powell's Washington state home for a planned supervised visit.
Powell brought the seven and five-year-old boys inside, but blocked the social worker from entering. She called her supervisors to tell them what happened, and that she smelled gas coming from the house. Moments later the house exploded in flames, killing Powell and the boys.
Powell earlier sent an email to his attorney saying, "I'm sorry, goodbye." Pierce County sheriff's spokesman Sgt. Ed Troyer told The Associated Press that Powell sent other emails that indicated that he planned the explosion. He would not go into detail on exactly what the messages said.
Powell denied having anything to do with his wife's disappearance, claiming he was camping with his sons that fateful night. But on Sunday the lawyer for Susan Powell's grandparents said the boys were starting to talk about what happened that night.
"They were beginning to verbalize more," said attorney Steve Downing. "The oldest boy talked about that they went camping and that Mommy was in the trunk. Mom and Dad got out of the car and Mom disappeared."
Family members are stunned by what happened on Sunday
"We never contemplated the idea he would do something like this. You just don't expect it from a father," said Kirk Graves, Powell's brother-in-law. "His world was falling apart around him and he was going to lose his boys and get arrested for Susan's disappearance. He's a narcissist and he has no love for anyone but himself."