Investigators said Josh Powell has recently stopped returning phone calls from authorities seeking his aid in finding Susan Cox Powell, though he appeared calm when they arrived at his two-story home in the suburbs Thursday afternoon. Detectives spent several hours combing through the house and vehicles, using disposable gloves in a search for evidence they said could propel the case forward.

Officials seized several computers while loading sealed boxes and bags into a mobile command center.

"We came here looking for specific things, and some of those things we’ve been able to find," West Valley City police Lt. Bill Merritt said Thursday night, about six hours after investigators arrived at the house. He called the evidence collected "very, very important" to the investigation.

Josh Powell is the only person of interest in Susan Powell’s disappearance, but he has not been charged or detained. He was allowed to leave the area with their children as investigators went through the property.

Police said the plan to search Powell’s home had been in the works for a while — since before a recent search through abandoned mines in Nevada. A few investigators thoroughly examined a van in the driveway, looking through every CD, flipping through scraps of paper and examining under seats.

Investigators declined to discuss what pieces of evidence they gathered.

"What we have here today will help us draw closer to a conclusion," Merritt said. "Whether it’s the conclusion that everybody wants and hopes for, we don’t know. It may be a conclusion that nobody wants to admit could happen."

The search came just hours after the case spiraled into an emotional saga pitting one side of Susan Powell’s family against the other.

Josh Powell’s father, Steve Powell, claimed in a nationally televised interview on Thursday that he had a flirtatious relationship with his daughter-in-law — something her parents adamantly denied, saying Steve Powell initiated unwanted sexual advances toward her.

Steve Powell told reporters outside the home Friday morning that investigators told him they were looking for Susan Powell’s journals — and they took his journals, as well.

"I didn’t want them to have my journals," he told KOMO-TV. "There’s very embarrassing things in my journals."

The Powell family, portraying Susan as promiscuous and emotionally unstable, offered as proof several diary pages from the missing woman’s teenage years. Her family says the entries were written by a young girl still growing up and have no bearing on her disappearance. They say they’ll sue if the Powell family publishes them as promised.

Josh Powell denied killing his wife or having anything to do with her disappearance.

"I would never even hurt her," a tearful, red-eyed Josh Powell told CBS’ Early Show. "People who know me know that I could never hurt Susan."

Josh Powell, who still wears his wedding ring, said he loves his wife. He said she came from an emotionally abusive home with controlling, manipulative parents.

In an interview on ABC’s Good Morning America, Steve Powell said he and Susan Cox Powell were falling in love and even implied a sexual relationship had occurred.

"Susan was very sexual with me," Steve Powell said. "We interacted in a lot of sexual ways because Susan enjoys doing that."

Susan’s father, Chuck Cox, told the AP that his daughter claimed years ago that "something had happened" with Steve Powell that made her uncomfortable. He said she didn’t disclose the details.

"She said something about Steve had wanted her to be a common wife for him and Josh," Chuck Cox said. According to him, when Susan discussed the remark with Josh, he dismissed it as part of his father’s penchant for saying outrageous things.

Chuck Cox said he believes his daughter’s discomfort with her father-in-law was part of what motivated her to move her family to Utah from Washington.

"She wanted as far away from him as possible," Cox said.

Chuck Cox, who also lives in Puyallup, denies allegations in court filings by Josh Powell seeking a protective order that he has harassed or threatened his son-in-law and said he only wants to spend time with his young grandchildren.

A court commissioner in Washington state Tuesday ordered Chuck Cox and Josh Powell to keep 500 feet apart.

Chuck Cox has never said he believes his son-in-law is responsible for Susan’s disappearance, but wants him to be more forthcoming with police, who claim Josh Powell hasn’t been cooperative.

"If he can get himself cleared, that’s fine with me," Chuck Cox said. "But he has obstructed the investigation of the police, he has refused to talk to them and there’s enough inconsistencies … they have to look into it."

Police say Josh Powell has refused to answer questions about a supposed midnight camping trip he said he took with the couple’s sons — then ages 4 and 2 — in the mountains west of Salt Lake City the night before Susan Cox Powell was reported missing.

Susan Powell was last seen by her husband Dec. 6, 2009, in her West Valley City, Utah, home outside Salt Lake City. She was reported missing the next day when she didn’t show up for work.

Alina Powell, Josh’s sister, has said her family has cooperated with the FBI, and will continue to do so, but they have nothing new to contribute. She said the family allowed its Puyallup home to be searched last year without a warrant.

The Powells also have been saying they believe the missing woman may have run off with another man, although Josh Powell said in interviews Thursday he doesn’t know if his wife was ever unfaithful.

He said he would like to tell his wife that he loves her and that her children love her, but he vacillates in his beliefs about whether she is still alive.

"It’s a rollercoaster," he told ABC News.

Chuck Cox said his family remains hopeful, but they are preparing "for the worst."