Fears of a violent gang are keeping some northern B.C. residents from sharing information about the torture and decapitation of a young man following a party last winter, CBC News has learned.

The severed head of Fribjon Bjornson, 28, was found in a vacant house on the Nak'azdli reserve near Fort St. James on Feb. 3, three weeks after he was last seen about 60 kilometres away at a 7-Eleven in Vanderhoof, B.C.

The rest of his body was never found and no one has been charged in the case.

Police have released new video surveillance recordings to CBC News that show Bjornson at the 7-Eleven the night he disappeared.

'If you don't come forward, you're part of it, because you allow it to continue.'—Fred Bjornson

They are hoping the video will prompt witnesses to come forward with new information about the case.

But Bjornson's parents say residents of the reserve have already told them what happened to their son. They say those same residents are unwilling to share what they know with police, in part, because of fear of retaliation by the gang.

Fred and Eileen Bjornson believe their son, who was a self-employed log processer and father of two, may have given a ride to the wrong person, which led to a robbery and his death.

Tortured and decapitated for cash

The family told CBC News they have heard that their son, who struggled with a cocaine addiction in the past, somehow ended up at a house on the reserve, where about two dozen people were partying on the night of his death.

On Feb. 3, 2012, RCMP investigators confirmed that the human remains located in a vacant property along Lower Road in Fort St. James on the Nak'azdli reserve were identified as Fribjon Bjornson, 28, of Vanderhoof, B.C. (RCMP)

They say residents of the area have told them four or five gang members attacked Bjornson in the basement of the house, perhaps after learning he had just cashed a paycheque worth several thousand dollars.

Bjornson was tortured, but his attackers went too far and he was killed, according to several sources who spoke to CBC News. His body was then dismembered, and the parts were disposed of, perhaps thrown into nearby Stuart Lake, which borders the reserve.

For some unknown reason his head was left in a nearby vacant house, where it was discovered three weeks later when investigators found Bjornson's abandoned truck nearby.

Police searched the two homes and the surrounding area, but no other traces of his body have been found.

The vacant house was later the focus of an end-the-violence march held by the community, and was smudged to release the bad spirits before it was torn down.

Parents ask witnesses to speak out

Bjornson's parents are pleading for anyone in the community who has information to tell police what they know.

"I can understand that they have a fear. But they need to overcome their fear and come forward," Fred Bjornson told CBC News.

"We don't have all of our son. We don't have all of our son's remains. They are somewhere," he said.

Fred and Eileen Bjornson believe their son died at a drug and alcohol-fuelled party on the Nak'azdli reserve. (CBC)

"The fact that somebody could do this to your child — it's unbelievable. It's like a nightmare you can't wake up from," said Eileen Bjornson.

"I don't know how you sleep with yourself at night. And if you don't come forward, you're part of it, because you allow it to continue."

Fred Bjornson says he believes fear of retaliation is keeping many witnesses from coming forward.

"There's a fear factor. Maybe they just don't want to be the one that comes forward because they'll be labelled in their community."

Witnesses not stepping forward

According to Chief Fred Sam, there are a lot of people on the Nak'azdli reserve who know something about the brutal killing of Bjornson.

"I guess probably maybe 20 or less, maybe, I'm thinking," Sam said. "It is quite a bit of people."

Last March, police issued a statement along with the Bjornsons for witnesses to come forward. Since then they have only said they are making progress in the case.

At the time, police said Bjornson had associated with people living a high-risk lifestyle. Cpl. Neil Stafford, of the RCMP's North District Major crime unit, now says police also believe witnesses are keeping quiet.

"The vast majority of people in these communities want to do the right thing," Stafford told CBC News.

Stafford is hopeful people will come forward with new information.

"People should have some reassurance in knowing the community would certainly be behind them and support them if they were to come forward with information."

The community of Fort St. James is also trying to find ways to solve Bjornson's death, along with other disappearances that have shaken the community.

Madison Scott went missing on May 28, 2011, after attending a bush party near Vanderhoof. Her truck and tent were later found at a campsite at Hogsback Lake, south of Vanderhoof.

Even though Scott and Bjornson knew each other, police and their families say they don't believe there are any links between the two cases.

The area is also linked to the surrounding communities by Highway 16, the so-called Highway of Tears, where at least 18 young women have disappeared or been killed, often while hitchhiking, over the last 40 years.

Bjornson's parents are now asking hunters and others in the woods to keep an eye out for anything of interest, including clothing, personal effects, even human remains, before winter snows cover what could be key evidence in the case.

"Please. Help me. Help me find my baby. Bring my son home," said Eileen Bjornson.