During a search of Josh Powell's storage unit on Thursday, police found a blanket with what appeared to be blood stains.

Detective Ed Troyer said the blanket was found when Pierce County deputies and West Valley City police conducted a joint search of a storage unit that Powell had been renting.

A preliminary test of the blanket, a grey, blue and pink comforter, was positive for blood.

"But that doesn't ... tell us whose blood it is or how it got there," Troyer said.

In addition to the blanket, which will require further testing at the state crime lab, police also found children's clothes and toys.

Before Josh Powell was going to try to win back custody of his children last week, Washington state authorities received materials from Utah police that had been discovered on a computer in Powell's home two years ago. Authorities say the images depicted "incestuous" sex and were disconcerting enough that they prompted a psychologist to recommend that Powell undergo an intensive psychosexual evaluation.

But a lawyer for Powell's in-laws, who had custody of the boys, wasn't invited to see the materials before the custody hearing, even though a Utah judge had specified in a sealed court order that he was one of the few people allowed to see them.

Had he seen the images, attorney Steve Downing said, he might have asked the court to change the terms of Powell's supervised visitation with the boys, such as by asking for the visits to be in a public place. Instead, Downing said he didn't learn until Thursday morning, four days after Powell killed himself and the boys in a house fire, that he was allowed to see them.

"That would have absolutely given me the opportunity to submit a declaration about our deep concern. I was approved ... to view those pictures and I was never notified," Downing said. "I could have gone into all the reasons why the visitation could have or should have been restricted."

Pierce County Sheriff's Detective Ed Troyer told The Associated Press on Thursday night that the images collected by investigators from Powell's home computer in Utah two years ago were realistic computer-generated depictions of "incestuous" parent-child relations. "It's family-oriented in nature," Troyer said. "It is incestuous."

"It was incest type activity between these animation characters and it appeared to be all family," said Troyer.

Troyer said the images couldn't be legally defined as pornography because they don't involve real people. Troyer said the judge in last week's custody hearing was apprised of the images at the proceeding.

Powell was the only person of interest in the disappearance of his wife, Susan Powell, from their home in West Valley City, Utah, in 2009. He was never arrested or charged in the case, and a month after she vanished, he moved with his boys back to his father Steve's home in Puyallup, Wash., south of Seattle.

Last year, authorities searched Steve Powell's home, computer and cars for evidence in Susan Powell's disappearance, and instead said they found thousands of voyeuristic pictures and videos, including child pornography recorded by Steve Powell. The state took custody of the boys and turned them over to Susan's parents, Chuck and Judy Cox.

Josh Powell repeatedly tried to regain custody of the boys. At one point late last year, he underwent a court-ordered psychological evaluation. The psychologist held off on finalizing his report for some time, anticipating that he would be able to review materials that West Valley City police had discovered on Josh Powell's computer, said Washington state assistant attorney general John Long, who represented the state in the custody case.

But as the Feb. 1 custody hearing neared, the materials hadn't arrived from Utah, Long said. It wasn't until after the psychologist finalized the report that the materials arrived at the Pierce County Sheriff's Department. When the psychologist saw them, he added an addendum to his report recommending the psychosexual evaluation of Josh Powell, an exam that can include a polygraph as well as more intrusive measures to determine the body's response to child pornography or other stimuli.

On Jan. 30, the sheriff's office arranged a viewing of the materials, said Sherry Hill, a spokeswoman for the Department of Social and Health Services.

Among the attendees were Long and a Child Protective Services social worker. Downing said he wasn't notified of the viewing. Long confirmed Downing had been listed as one of those allowed to see the images. However, Downing was not technically a party to the Feb. 1 hearing, which was between Powell and the state, so there was no rush to make sure Downing saw the materials beforehand.

Josh Powell's attorney, Jeffrey Bassett, also did not attend. He said in an email Thursday that there had been some "miscommunication," and he didn't learn about the viewing until after the fact. He wasn't able to immediately schedule another viewing.

Two days later, Pierce County Superior Court Judge Kathryn Nelson heard arguments from Josh Powell seeking to regain custody of his children. Long opposed that, noting only that "concerning" images from his computer had been provided by the police in Utah.

After considering Long's arguments and the recommendation for the psychosexual evaluation, Nelson denied Powell's request. She said she wouldn't consider granting Powell custody unless he underwent the exam. She didn't make any changes in the visitation schedule, which allowed Powell to see his boys, 5 and 7, at his house twice a week while supervised by a social worker.

On Sunday, the social worker brought the boys to see their dad at his rental home outside Puyallup. After the boys rushed inside, he slammed the door in her face, locking her out. He attacked the boys with a hatchet, then torched the home in a gas-fueled inferno.

Chuck Cox, Susan Powell's father, said the images were just another indicator of problems with Josh Powell. Cox said he did not know the details of the images. He believed the kids should have been fully taken away from Powell long ago and that they raised concerns about allowing him continued contact.

"How much does it take for them to figure out that he should not have the children?" he said. "It's just wrong. They needed to be taken out of that environment."

The Associated Press contributed to this report.

Chris Sullivan, 97.3 KIRO FM Reporter

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