GRAHAM, Wash. — Officials say an explosion at a Washington state home has killed Josh Powell, the husband of a missing Utah woman, plus their two young sons.

Graham Fire and Rescue Chief Gary Franz tells The Associated Press that explosion occurred moments after a Child Protective Services worker brought the two sons of Susan Powell to the home for a supervised visit.

He says Josh Powell let the boys in the house, then blocked the social worker from entering.

The social worker called her supervisors to report that she could smell gas, and the home exploded.

Authorities suspect Josh Powell of blowing the house up on purpose.

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