The NSW man and his girlfriend shot dead on a notorious Canadian road, where dozens of other people were also murdered or vanished, has sparked fears a serial killer is on the loose.

Australian Lucas Fowler, 23, and his American girlfriend Chynna Deese, 24, were found dead on the Alaska Highway, in the northern part of British Columbia on Monday about 7am (local time).

Lucas Fowler and his American girlfriend Chynna Deese, were found dead on the Alaska Highway in British Columbia, Canada on Monday. Source: NSW Police

Serial killer link to Highway of Tears murders

Some media reports have raised the prospect of a serial killer linked to the murders, with the couple being the fifth victims on the road in just one year after three women died or disappeared in 2018.

However, the freeway where more than 40 people have been murdered or went missing is located 1,000km south of where Mr Fowler and Mr Deese were killed.

Local authorities believe claims of a serial killer are false.

"This investigation is in its very infancy and it is not yet clear whether Lucas and Chynna were targeted or if this was a crime of opportunity,” Sgt Janelle Shoihet, of The Royal Canadian Mounted Police, said at a press conference Friday.

“At this point, we have nothing to indicate that their deaths are linked to any other active and ongoing investigations in the area, or if there is a heightened risk to public safety,” the Alaska Highway News quoted her as stating.

“Our investigators will consider any and all information carefully as the investigation progresses.”

Canadian authorities have denied fears Lucas Fowler and Chynna Deese were murdered by a serial killer. Source: NSW Police

Alaska Highway murderer has a ‘head start’

"I don't think it's a serial killer," Ms Deese's father, Dwayne, told the Charlotte Observer newspaper.

"I think of someone who has been convicted of violent crimes before, someone on drugs.

"What worries us is that person is still on the loose and they have a head start.

"This is going to happen again.

"There needs to be some kind of a warning system in place for tourists."

The RCMP is leading the hunt for the killer.

Mr Fowler's father Stephen is one of NSW's most senior police officers, is joining other family members to fly to Canada "to be with our boy and to bring him home".

The NSW Police has sent two homicide detectives to Canada to assist the investigation, liaise and support family members.

Family members of Ms Deese have posted heartfelt messages online, describing her as an “amazing life companion” who made those around her smile.

“Life throws curveballs and you made every one easier to handle. This is a curveball I did not expect,” he brother wrote.

“Losing you is going to hurt so much.”

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