Utah investigators handling the case of missing mother Susan Powell examined her father-in-law's cell phone, calendar and emails earlier this year.

 Records obtained by The Associated Press show that the intensive effort began in April after a former co-worker of Steve Powell's said he had talked about traveling to Utah in the weeks close to when she went missing.

Susan Powell's father, Chuck Cox, told KIRO 7 Eyewitness News in April be believed Steven Powell was complicit in his daughter's presumed death and that he may have been "the one who did it."

 Investigators had largely focused on Susan Powell's husband, Josh, who killed himself and the couple's two young children earlier this year. Utah investigators said they can't discuss details of the case, but Washington state officials have said they believe Josh Powell killed his wife. They also say his father may know more about the disappearance than he's letting on.

An attorney for Steve Powell didn't return a call seeking comment.

Steve Powell was sentenced to 30 months in prison after he was convicted of voyeurism for taking photos of young girls.

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