Two more people are missing from the same stretch of road where Australian man Lucas Fowler and his American girlfriend Chynna Deese were murdered.
Mr Fowler, 23, and Ms Deese, 24, were the victims of a violent murder that left them unrecognisable after the van they were travelling in broke down on Canadian Highway 97 on Sunday.
The pair were found a short distance from their blue 1986 Chevrolet van on Monday morning.
Police also found another man dead a short distance up the road next to a burnt out vehicle. But in a shocking twist, they now say the man was not the vehicle's owner and that the two teens travelling in that vehicle are missing.
In a statement, the Dease Lake Royal Canadian Mounted Police said they have been unable to locate Kam McLeod, 19, and Bryer Schmegelsky, 18.
"It is unclear at this time how this deceased male might be connected with vehicle fire or the two missing men," police said in a statement.
"At this time, investigators are sharing information and police would like to ensure awareness around both investigations.
"The RCMP would ask the public to continue to take any general safety precautions and remain vigilant at this time."
The news comes as a new photo of the van Mr Fowler and Ms Deese were travelling in shows the back window has been smashed in or shot out.
Family members of the victims have begun speaking out as a massive manhunt enters its second week amid fears a serial killer is on the run.
Mr Fowler's father, NSW Police Chief Inspector Stephen Fowler, has arrived in the US along with two experienced NSW homicide detectives.
He told Nine News the family was "crushed". He said his son was "just a wonderful boy".
"It's just so devastating … we're just crushed," Insp Fowler said.
Ms Deese's brother British Deese spoke with Sunrise this morning from his home in Charlotte, North Carolina, revealing details of the couple's plans. He said the trip they were on was no different to previous adventures.
"They have gone on road trips around the country, across North and South America. This is just what they did and loved doing together," he said.
"This wasn't any different … it wasn't really anything different from what they have done for the past one-and-a-half years. In seeing all the national parks and travelling up the Alaskan highway seeing what they can."
Mr Deese said something went horribly wrong and the family was struggling to get answers.
"I know there was at least somebody who saw them while they were breaking and pulled off the side of the road and asked if they needed help," Mr Deese told the program.
"Maybe the van overheated and they were waiting for it to cool down. They were planning on getting back on the road and they didn't feel like they needed help or anything."
"Something happened and it was unexplained after that. That is the extent of what anyone knows for the most part. It is really very frustrating."
Police are searching for a vehicle that belongs to a mystery bearded man seen arguing with the couple before they were murdered.
A witness told Nine News they saw the man in a heated exchange with the pair on the side of the road.
But Ms Deese's father Dwayne Deese says he doesn't believe a serial killer is on the loose.
"I don't think it's a serial killer. I think of someone who has been convicted of violent crimes before, someone on drugs. That fits the profile better," Mr Deese told The Charlotte Observer.
"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."
Royal Canadian Mounted Police Corporal Chris Manseau told the Associated Press on Sunday it was unusual for "these events" to occur in that remote part of Canada.
"Northern (British Columbia) is a really big area and yet they don't have a lot of these events," he said.
"Two of them have happened within a couple of days of each and people want to speculate.
"The last I heard there was nothing to tie either of those two together although investigators are looking at all of the leads."
The second event he referred to was the death of a man found further along the highway on Friday near a burning vehicle. Police have stressed they have no information to link the two events.
Passing motorists Curtis and Sandra Broughton were the last people to see Mr Fowler and Ms Deese alive. The Canadian couple stopped to offer assistance just before 3.30pm on Sunday.
Mr Broughton, a mechanic, said he spoke to Mr Fowler, but the 23-year-old seemed to know how to fix the van.
"The vehicle was flooded out and they were going to try and get it going again until they could get the parts they needed," Mr Broughton told AAP.
The Broughtons got back in their car and drove home.
Mr Fowler and Ms Deese were found dead the next day.