Five days after a Utah mother's disappearance, puzzled police are calling the case suspicious and plan to question the woman's husband a second time.
Susan Powell, 28, was last seen Sunday at her home in West Valley City and was reported missing by relatives the next day.
Powell's husband, Joshua Powell, and two children were also believed to be missing but returned home Monday afternoon. Joshua Powell said he decided Sunday night to take the children on a late-night camping trip.
"Lots of times I just go camping with my boys," Powell told a local CBS News' affiliate. "Just overnight. We do s'mores and stuff."
But after not hearing from her for five days, Susan Powell's family has become worried.
"I don't think she's OK. No one has heard from her," Susan Powell's father, Charles Cox, said. "Josh and the boys are back, and she wouldn't leave her children."
The West Valley City Police found her purse and keys in her bedroom.
"The suspicious nature of this is that no one can tell us, or is [willing to tell] us her whereabouts, and she has not contacted us or anyone we know about," Capt. Tom McLachlan told the Salt Lake Tribune.
Police officials interviewed Joshua Powell, as well as the couple's 4-year-old child, but walked away with more questions than answers, they told ABC News.
"He did give us a statement, and we're following up on all aspects of that statement," McLachlan said.
Joshua Powell is not a suspect, police said. Powell declined to comment to ABC News.
Police said neither Susan nor Joshua Powell called into work Monday to explain their absences. The husband later said he had been confused about what day it was, according to a CBS News report.
Susan Powell's Father: Couple Had Marital Problems
Cox, Susan Powell's father, said he still has a lot of questions, including why his son-in-law would take his two young children, ages 4 and 1, camping in a snowstorm.
There are no reports of domestic violence, but, Cox said, the couple had marital problems and were trying to work them out.
"They have had issues in the past … but they had been talking to each other and, according to my daughter, things were getting better," Cox said.
Police urge anyone with information regarding the case to call West Valley City Police at (801) 840-4000.