Amber Hardman / Hardman Photography via AP

Susan Powell, the Utah mom who went missing in 2009.

TACOMA, Wash. -- Authorities investigating the 2009 disappearance of a Utah woman found her blood in the family home and a hand-written note in which she expressed fear about her husband and her potential demise, according to documents unsealed Friday.

The files raise further questions about why Susan Powell's husband was never charged in her disappearance before he killed himself and their two young sons in a gas-fueled inferno in Washington state earlier this year. Investigators in West Valley City, Utah, never arrested Josh Powell or even publicly labeled him as a suspect in Susan Powell's disappearance.

A prosecutor in Washington state who was getting a first look at the files Friday said if it was his case, he would have charged Josh Powell with murder.

"There is direct evidence. There is circumstantial evidence. There is motive," said Pierce County prosecutor Mark Lindquist. "There is everything but the body."

The documents, used as justification to search the home where Josh Powell was staying last year, detail a widespread case that investigators had built against him.

Shortly after Susan Powell disappeared, authorities found blood evidence on a floor next to a sofa and determined that it was Susan Powell's. They found several life insurance policies on Susan Powell that totaled $1.5 million. The documents describe Josh Powell as unwilling to help in the investigation.

A safety deposit box used by Susan Powell had a hand-written letter titled "Last will & testament for Susan Powell," according to the documents. She wrote in that letter that she did not trust her husband and that they'd been having marital troubles for four years.

The letter also said that "if Susan Powell dies it may not be an accident, even if it looks like one," according to the documents.

Josh Powell always maintained his innocence and said he had taken their boys, then 2 and 4, on a midnight camping trip in freezing temperatures the night she disappeared.

Cops: Josh Powell murder-suicide house was sham

One of the children, Charlie, told investigators in an interview shortly after Susan Powell disappeared that she had gone on the camping trip with them but did not come back home and did not know why, according to the files. A few weeks later, he told a church teacher with no emotion: "My mom is dead."

Pool / Getty Images

Photos of Charlie Powell, right, and Braden Powell are displayed during their funeral service on Feb. 11.

Powell moved with the boys to his father Steve's home in Puyallup, Wash., but Steve Powell was arrested and charged with voyeurism and child pornography last September. The boys were placed with Susan Powell's parents for their safety.

On Feb. 5 — a few days after incestuous images found on his computer prompted a judge to order him to undergo a psycho-sexual evaluation — Josh Powell locked a social worker out of his rental house, attacked the boys with a hatchet and then ignited the home in an explosive, gas-fueled inferno. The social worker was not injured.

Charlie Powell was 7; Braden Powell was 5.

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