( CNN ) -- Initial tests detected blood on a comforter found in a storage unit in Washington state belonging to Josh Powell , the man who police say killed his two sons and himself , according to a document filed Friday . It was not immediately clear who the blood belonged to or how much investigators found on the comforter , which was among the items inside a unit at Western Self Storage in Sumner , Washington . The property report from authorities indicated succinctly that a `` presumptive test '' of the comforter had tested positive for blood . Prior to setting a deadly fire Sunday at his Puyallup , Washington , home , Josh Powell was the only person identified by law enforcement authorities in West Valley City , Utah , as someone they were investigating in the disappearance of his wife , Susan Cox-Powell . According to a search warrant request by Pierce County , Washington , Sheriff 's Detective Ryan Salmon , last Sunday `` several people began calling 911 saying they had received e-mails from Joshua Powell , telling them goodbye , that he could not live without his kids , and to take care of several things related to his finances . '' Before authorities arrived , Powell is accused of snatching his young sons from a social worker who was delivering them for a supervised visit , locking the door , hacking the kids with a hatchet and starting an explosive fire in the home . The search warrant request noted that the medical examiner 's office found `` sharp impact wounds ... on the back of the head of the two children , '' that a hatchet was recovered near their bodies , and that `` accelerant was apparently used on the bodies . '' According to the detective , Powell last visited the storage unit on the day before he was accused of committing the double murder-suicide . That same day , he withdrew $ 6,500 in cash from a bank -- money that is `` unaccounted for , '' the document said . In addition to the comforter , authorities took two plastic bins with miscellaneous items , a box with blocks , a white garbage bag filled with children 's clothes and linens , another bag with toys and framed photos from the storage unit . Most of those items were handed over to relatives of Cox-Powell , the property report states . Funeral services for the two slain boys -- Charlie , 7 , and Braden Powell , 5 -- will be held Saturday . Josh Powell had said that he last saw Susan in December 2009 , after he and his two sons left after midnight to go camping in below-freezing weather in a desert area in Tooele County , Utah . Cox-Powell 's sister eventually reported the mother , who would now be 29 years old , as missing . A month later , Powell and his children moved from Utah to Washington .
Washington authorities search a storage unit belonging to Josh Powell . A `` presumptive test '' of a comforter found inside the unit detected blood . Powell 's wife has been missing since December 2009 . Police say Josh Powell killed his two sons and himself last Sunday .