North Dakota cold-case mystery: Who killed Anita Knutson?

"Anita was the coolest girl. Everybody at school loved her. I was really lucky to have her as my sister," said Anna Knutson, Anita's younger sister.

When she was just a baby, Anita was taken in by Gordon and Sharon Knutson, and her adoptive siblings Daniel and Anna soon followed.

At only 18, Anita was living on her own, working two jobs, and putting herself through college at Minot State University in Minot, North Dakota.

Many people wanted to be close to Anita. Until someone got too close.

"I talked to her Friday," said Anita's mother Sharon. "She said she was going home. That was the last time I talked to her."

The next day, Anita stays home from her job at a local hotel.

"I called her Saturday just out of habit of calling her every day, almost, and she didn't answer," said Sharon. "So I called Sunday -- no answer Sunday, and so Monday I called her and still no answer, and she should have been answering her phone."

After that, Sharon asked her husband to drive out to Anita's apartment to check on her.

"I went and knocked on the door, didn't answer, and her car was there," said Gordon. Gordon tries to let himself in, but the door is locked. "So I went to the apartment manager and said that I wanted her to open the door. First she said she couldn't do that because she could get in trouble. And I said well I think you'll get in trouble if you don't."

"They go to where the window was and I seen somebody laying in there and I walked over and the window is open, and I touched her head and I said 'You get that door open right now,'" said Gordon.

Inside the apartment, no signs anything sinister happened, until they get to Anita's bedroom.

"The mattress was soaked with blood. She was covered up with a large house coat. She was laying face down on the bed," said Gordon. "I touched her and her body was cold. So I knew she was dead and from that point I think I was just in total shock."

It's in that state of shock that Gordon has to give the rest of his family the news.

Police arrive a short time later and begin scouring the crime scene.

"According to the forensics crime lab, said that she was killed on Sunday morning," said Minot Daily News reporter Kim Fundingsland. "It was with a pocketknife, a three- or four-inch blade, I would suspect -- multiple stab wounds to the chest."

In what seems like a stroke of luck, investigators actually find the murder weapon, a cheap novelty pocketknife, at the foot of Anita's bed. But the motive for her murder is much more elusive.

To get answers, police start looking at the people closest to Anita, and few seemed to stick closer than that her high school senior prom date Tyler Schmaltz.

In fact, to find him, detectives don't have to look any farther than just outside the taped-off crime scene.

It was just a onetime thing, but according to some people, Tyler stayed a little too close after prom, even moving into Anita's apartment complex after high school.

And after her death, Tyler only got closer, creating a Facebook page in her honor and creating a 20-minute-long tribute video to Anita on YouTube.

"She was my best friend back in high school and the beginning years of college," said Tyler Schmaltz. "We went to high school together, we went to our senior prom together.

"Not dating. I just had a crush on her," said Tyler. "We were just friends.

"[Police] interviewed me the very second I got up there," said Tyler. "When they first interviewed me, it was actually at the crime scene, in the van. They were concerned because I knew exactly when I last talked to her, they kept asking me about that, but that's because when I got up there the first person I saw was her aunt. And her aunt asked me when the last time I talked to her, so I went on my computer and checked my chat logs. They just kept hounding me on that. But then they just asked general questions."

A month later, police brought him in again.

"They were interviewing everybody in the apartment complex including me and my brother, who lived with me," said Tyler. "They took DNA samples from all of us."

The results of those tests were never made public, but authorities say they never made a match to any DNA found at the scene, and Tyler claims he was cleared as a suspect.

"She was just so amazing, she just meant that much to me," said Tyler. "Back in my first days of college, all my high school friends moved away and she was my only friend I had then. I'm a quiet shy guy and I'm not that much outgoing, so at that time she was my only friend. She was just the most amazing person in the world, and she didn't deserve any of this."

Shortly after news of the murder breaks, a witness tells police he saw a man running away from the area around the time Anita was supposedly murdered. Investigators release a sketch of the suspect, and almost immediately get a hit.

"That person came forward right away as soon as he saw the drawing was published and resembled him, he came forward and was cleared immediately," said reporter Kim Fundingsland.

It turned out he was just a jogger out on his normal route at his normal time.

"There was some maintenance men working on a building nearby doing roofing, temporary workers in the area doing roofing, that left. It was thought that perhaps one of those people could have been involved in that," said Fundingsland.

But police questioned those men as well, and no one was charged.

"The only thing that comes to mind is the janitor who had access, because he was the maintenance man on the apartment complex, and he was dating the supervisor of that complex," said Tyler.

Anita's dad, Gordon, says he was the man who found the screen to Anita's bedroom window. And in a tragic twist some might consider suspicious, the man reportedly killed himself roughly a year after Anita's murder. But Minot Police have said they questioned him thoroughly and don't believe he had anything to do with it.

Investigators did have another person in their sights, someone physically closer to Anita than almost anyone else, and she just happened to be one of the few people Anita had anything bad to say about.

"She had a girl roommate and they didn't get along," said Anita's mother, Sharon. "That person was not a safe person. She would have male friends over and then Anita would tell me she would leave and leave the male friends there, whoever they might be.

"According to Anita, on her cellphone, this [roommate] person would text to her threatening letters," said Sharon. "Anita was scared of her. She was planning on moving out."

As police looked into every possible motive for Anita's murder, her family would be hit with another horrible tragedy.

Reports were that Anita and her roommate fought over almost everything. Police say at least one of those fights actually turned physical when the roommate slammed Anita's foot in a door. Anita's mom even says that after receiving numerous threatening texts from the roommate, her daughter said she was afraid for her life.

"The day of the funeral this roommate's mother came to me and was very upset because the police had requested that this roommate go down to the police station that day," said Sharon.

But what police found was that the roommate had a solid alibi. She'd been staying with her parents on the other side of town the entire weekend. Police still took DNA swabs from the girl, but had nothing to hold her further.

Anita's father also says that at the time of her death, Anita and the roommate had patched things up, though he does wonder about another possible connection: The person Anita was thinking of moving in with when things were at their worst in the apartment.

"And I said you're not going to move in with so-and-so? And she said 'No,' she says, 'I wouldn't move in there anyway because of her husband,'" said Gordon. "If he was hitting on her, she didn't go for that. She would have probably said she was going to tell her friend."

The family passes that info and multiple other leads on to investigators, and tips roll in regularly from the public. But even with the actual murder weapon in custody, the case goes cold.

Anita's family tries to move on with life, but Anita's adopted brother Daniel can't cope with the loss.

"I talked to him the day before he committed suicide, and he was fine, and he said he'd talk to me later, and then the next day, he was gone," said Sharon. "He shot himself."

Crime Watch Daily tried to set up an interview with Minot Police, but they initially declined the request, citing scheduling conflicts.

Local reporter Kim Fundingsland, close to the investigation, was able to offer the inside scoop.

"I don't know if they've dropped the ball, and I don't know if they've interviewed everyone they should interview," said Fundingsland. "I think police have their work to do, and you never know for sure what they've done behind the scenes."

After again reaching out to Minot Police, Crime Watch Daily got them to sit down in front of our cameras.

"I know the Minot Police Department has taken criticism from family members, friends of Anita's, the community," said Minot Police Detective Sergeant David Goodman. "People don't like to see crimes like this go unsolved. We understand that. We're sorry for that. And we really wish that we could come up with the answers for the family."

"We recovered DNA evidence from the crime scene in general, including the knife," said Ward County Sheriff's Chief Deputy Robert Barnard. "Nearly everyone that we interviewed submitted to a DNA sample, and all those samples have been compared to the DNA collected from the crime scene."

In addition to what they say has been thorough evidence collection, police tell us they questioned as many people as they could find.

"We talked with workers from the apartment complex prior to the homicide," said Barnard. "A construction company had been doing some work on the building. I don't know if we got all those guys or not. I hope that we did, but it wouldn't surprise me that there might have been a few that we did not interview."

"Anita liked to go to a dance club downtown. We went through their list of customers, patrons, with a fine-tooth comb," said Goodman. "We were not able to locate anything that led us in any promising direction."

"The window leading into Anita's bedroom had a screen on it that was cut. And I believe that that was something done after the fact," said Goodman. "There was some blood found on the cut of the screen which certainly leads me to believe that it was done after the fact."

"I believe the purpose would be to mislead law enforcement, to try and show that this is possibly an entry point," said Det. Goodman.

But why? And how did they get in if not through the window?

"The main door was locked, so I believe that whoever committed the murder either locked the door on their way out, or if it was locked when they arrived, they would have to had some way to get in, such as a key," said Goodman.

And the list of people who had keys to the apartment is a short one. Is the roommate still a suspect? Crime Watch Daily producers have made an attempt to locate and speak to the girl, but have so far received no response.

"I don't know that we really ever discounted any of the suspects that we came up with," said Goodman. "Everybody, until we get new direction in this case, is still somebody that could possibly be involved."

Police say new scientific advances may be getting them closer to finding that somebody than ever before.

"We have been in contact with the state crime lab, and since 2007 there's been advances in technology, so they are taking another look at their DNA in that case," said Minot Police Captain John Klug. "I think now enough time has passed that if we try to run DNA on that knife again, that there could potentially be something found."

For now, in addition to the police effort, Anita's one-time prom date, Tyler, continues to work his own citizen investigation, which has yielded some very interesting results.

"I just received a new tip today that I haven't gave to them yet," said Tyler Schmaltz. "Some random person contacted me on Facebook saying that this one person told her that this sex offender who's been in and out of prison, someone at a party told her that he's the one who killed Anita."

Crime Watch Daily has not yet been able to verify whether or not police have followed up on that tip, but they assure us they continue to chase down every lead they receive.