Josh Powell Update: Documents report Powell killed pets, threatened mother with knife as a teen

(CBS) PUYALLUP, Wash. - New information about Josh Powell's past came to light last week when the Salt Lake Tribune newspaper reported that documents from Powell's parents' divorce two decades ago portray the then-16-year-old as seriously troubled. 

Pictures: Missing Utah mother Susan Powell

According to the Tribune, the documents state that a teenage Powell had tried to commit suicide, threatened his mother with a butcher knife, and killed pet gerbils.

Powell and his two sons were found dead in his home on Feb. 5. Powell reportedly attacked the boys with a hatchet then set the home on fire.

Powell had been a suspect in the disappearance of his wife, Susan, who has been missing since December 2009. 

On Friday, police found a comforter stained with blood in a storage unit rented by Powell, reported CBS affiliate KIRO.

According to KOMO TV, investigators received a tip that Powell may have dumped some papers at a recycling center a few days before committing murder-suicide. But a search of the nearby landfill Sunday did not reportedly yield any significant evidence.

Last week, authorities announced that they had discovered "incestuous" images on Powell's home computer.

Josh Powell's father, Steve Powell, was arrested on child pornography charges. According to the Tribune, pornography was raised as one of the issues in the Powell's divorce.

Two days after investigators found a blood-stained comforter in a storage unit rented by Josh Powell, investigators sorted through mounds of recycled paper at a landfill in hopes of finding papers he may have dumped before killing his two sons and himself last week.

Complete coverage of the Susan Powell case on Crimesider