Source: 'Rage Killing' in Hacking Home

Investigative sources believe that a "rage killing" took place inside Lori and Mark Hacking's apartment hours before Lori was reported missing, FOX News has confirmed.

Authorities also said they believe Lori Hacking (search) was attacked and killed inside the apartment.

Police confirmed that a bloody knife with strands of brown hair on it was among the numerous pieces of evidence they removed from the couple's apartment.

There were also unconfirmed reports that authorities were testing a clump of brown hair found in a trash bin just a block or two from the store where Mark Hacking purchased a mattress minutes before he called police about his wife's disappearance.

There were additional rumors that authorities, using blood-detection techniques, found a significant amount of blood inside the Hackings' home.

Detective Dwayne Baird wouldn't confirm the reports about the evidence, but didn't deny them either.

On Tuesday, police completed their search of the apartment. The families of the missing woman and her husband began packing up and moving out the couple's possessions.

The couple were planning to leave their Salt Lake City home last week and move to North Carolina, but Lori Hacking disappeared just days before, apparently on July 19.

Overnight Monday, authorities hunting for evidence in the case returned to a previously searched landfill, this time with cadaver-sniffing dogs.

They wouldn't say whether they'd found anything when they re-examined the area near Salt Lake City.

Meanwhile, a spokesman for Lori Hacking's family said the search for the 27-year-old woman would not take place Tuesday. Spokesman Scott Dunaway said the decision had nothing to do with the landfill search.

Instead, plans were in the works for a later search using specialized teams, possibly with volunteers on all-terrain vehicles, according to Dunaway. He said the family is thankful to those who have been helping, but they've become concerned about the volunteers' safety.

In other developments, police confirmed news reports that Lori Hacking's last day at work before she disappeared was cut short by a phone call that left her so distraught she went home early.

"We wouldn't have any reason to doubt" the Wells Fargo employee accounts, Baird said Monday.

Hacking's co-workers said the normally private young woman was sobbing after the University of North Carolina (search) medical school called to say her husband Mark Hacking (search) was not enrolled there, as he had told her.

The couple was to move to North Carolina just days after Lori disappeared, and she'd been trying to arrange on-campus housing.

"She was visibly upset. She started to cry and got up to walk away," her supervisor, Randy Church, told The Associated Press on Monday.

He added that when co-workers asked her what was wrong, she replied, "It's no big deal; I'm OK. But I think I will go home."

Mark Hacking, 28, who has been hospitalized since early Tuesday in a psychiatric unit, has retained high-profile defense attorney D. Gilbert Athay.

Athay said Monday he has spoken to Mark Hacking many times since being hired Thursday. He refused to characterize the conversations.

After Lori Hacking vanished, police and family members learned that besides lying about being accepted to medical school, her husband had not even graduated from college.

Lori Hacking left work early after receiving the call Friday afternoon, July 16. Mark Hacking reported his wife's disappearance the following Monday. He has become the focus of the police investigation.

Mark Hacking has been at the psychiatric hospital since police found him running around naked in sandals the night after the search for his wife began. Police refused to say whether he was being held involuntarily.

His wife, a trading assistant who had just learned she was five weeks pregnant, was a private woman who did not share personal troubles, making her breakdown in the office all the more unusual, said colleagues at Wells Fargo Securities Services (search).

Lori Hacking's co-workers gave accounts of the phone call to homicide detectives after she was reported missing. Officials at the University of North Carolina were trying to determine whether one of their administrators made the call.

Baird would not comment further, but later dismissed suggestions that an arrest was imminent.

"Our most important focus in this case is the fact we have a missing person and, coupled with that, it's under very, very suspicious circumstances," he said.

Church said detectives showed up at Wells Fargo the day after Hacking's disappearance and inspected her e-mail and computer files. Results on some of the other evidence collected by police, including a mattress recovered from a trash bin and a box spring taken from the couple's apartment, are pending.

Mark Hacking said his wife did not wake him up after coming home from an early morning jog July 19 and never showed up to work.

Police later said he was at a furniture store buying a new mattress only about a half an hour before reporting that Lori was missing.

Footage from a surveillance camera shows Mark Hacking looking for a mattress in one store but then leaving, apparently when he found out he couldn't take his purchase with him right then, FOX News has learned.

Instead, he wound up buying the mattress he came home with from a store across the street.

The families of both Lori and Mark Hacking have been holding as many as two news conferences a day since Lori was reported missing. But they have been more reluctant to face reporters since questions arose about Mark's credibility.

Mark Hacking's family said they'd visited him in the hospital as recently as Sunday and he was doing well, asking for video games to pass the time and inquiring frequently about the investigation. They also said they have been careful about what they've been telling him.

Fox News' Alicia Acuna, Catherine Donaldson-Evans and The Associated Press contributed to this report.