'Heated exchange' with mystery man before couple found dead on highway

A mystery bearded man was reportedly seen in a “heated exchange” with an Australian man and American woman the night before their bodies were found along a remote Canadian highway last week.

Lucas Fowler, 23, from Sydney, and his girlfriend Chynna Deese, 24, from North Carolina, were found shot dead last Monday along the Alaska Highway in the northern part of British Columbia after their blue 1986 Chevrolet van broke down.

Road worker Alandra Hull told Nine News she saw Mr Fowler and Ms Deese on the highway the night before they were found dead, talking with a man who "kind of looked frustrated or something".

She said the man was standing in the middle of the highway with his arms spread, while Mr Fowler and Ms Deese stood beside their van visibly bothered.

"If you just get a bad feeling, and that's what I had, you just don't stop," she said.

Ms Hull has since passed on her witness account to police and will now assist an artist to create a composite image of the man.

Fellow road worker Trevor Pierre, who is also a paramedic, was called out to where the bodies were spotted by passing tourists.

He told Nine News he was shocked at what he found, and the image of the bodies lying on the roadside was still vivid in his mind.

"I don't know how anyone could live with themselves after doing what I saw," he said.

New image of couple’s damaged van

Journalist Nadia Stewart shared a new photo of the couple’s van with its rear window on the back right door had been smashed and covered with a black sheet.

Adding to the mystery, the body of a man was found on Friday near a burning pick-up truck south of the Stikine River Bridge on Highway 37 in northern British Columbia.

"Northern BC is a really big area and yet they don't have a lot of these events," RCMP corporal Chris Manseau told AAP on Saturday.

"Two of them have happened within a couple of days of each other 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 RCMP have released few details about the Stikine River Bridge death and the shooting deaths of Mr Fowler and Ms Deese.

His father, NSW Police chief inspector Stephen Fowler, has since arrived in Canada, revealing his family are “crushed” over the deaths.

Two NSW homicide detectives also travelled to Canada to help as liaisons.

The Fowler family is expected to meet Royal Canadian Mounted Police investigators in British Columbia for an update.

Couple recall meeting pair before their deaths

Mr Fowler and Ms Deese were on a Canadian road trip last Sunday on the Alaska Highway, 20km south of Liard Hot Springs, when their old van broke down.

Passing motorists saw them, including Canadian couple Curtis and Sandra Broughton who stopped to offer assistance about 3.20pm on Sunday.

Mr Broughton, a mechanic, said he spoke to Mr Fowler but the young Australian 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.

RCMP investigators want to speak with anyone who may have been travelling near Liard Hot Springs on Alaska Highway 97 between 4pm Sunday and 8am Monday.

They are particularly interested in motorists with dashboard cameras who may have been filming.

RCMP would also like to speak to anyone who was staying at camping sites in the area.

With AAP

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