Canadian police say they have found two bodies they believe are the teenagers suspected of murdering three people, including Sydney man Lucas Fowler.

Key points: Police are "confident" the bodies are of the two teens suspected of killing three people

Police are "confident" the bodies are of the two teens suspected of killing three people But they say an autopsy will be conducted to confirm the identities

But they say an autopsy will be conducted to confirm the identities Australian man Lucas Fowler and his American girlfriend were among those killed

Kam McLeod, 19, and Bryer Schmegelsky, 18, were wanted in connection with the July 15 murders of Mr Fowler, 23, and his American girlfriend Chynna Deese, 24.

They were also charged with the murder of university lecturer Leonard Dyck, 64. All three bodies were found in the province of British Columbia, on Canada's west coast.

Royal Canadian Mounted Police (RCMP) Assistant Commissioner Jane MacLatchy said the bodies believed to be the wanted teens were found in dense scrub in Manitoba, 1 kilometre from where "several items directly linked" to the fugitives were found, and 8 kilometres from where a grey Toyota RAV4 they were known to have been driving was found in flames on a highway.

Assistant Commissioner Jane MacLatchy told journalists that police believed the two bodies were the fugitives. ( AP: David Lipnowski/The Canadian Press )

Assistant Commissioner MacLatchy said she was "confident" the bodies were the two suspects but told reporters an autopsy would be completed to confirm the identities.

"To the families of everyone affected by the series of events over the last few weeks, I know it has been so very difficult and I hope today's announcement can begin to bring some closure," she said at a press conference in Winnipeg.

"Your lives have been disrupted. Many of you lived with uncertainty and fear but throughout you were resilient.

"You came together as communities and you helped our officers get the job done."

Ms Deese's brother, British Deese, said the family needed time to process the news that the suspects' bodies were apparently found.

"We are speechless," he said in a text message, declining further comment.

Gillam Mayor Dwayne Forman said people in the community had been on an emotional roller-coaster and were relieved the manhunt was over.

"The closure is here for Gillam and the Fox Lake area. But the closure for the victims' families is far from over," he said.

RCMP Manitoba tweeted that the discovery of items on the banks of the Nelson River had allowed officers to narrow the search and eventually locate the bodies.

A police helicopter had initially spotted a damaged boat along the river last week in what Assistant Commissioner MacLatchy described as "very tough terrain".

On Sunday, RCMP sent dive teams into the river, which is wide, fast-flowing and powers several hydro-electric dams, however the underwater search proved futile.

Police have not said what items were found on the bank of the river.

Sydney victim Lucas Fowler was found dead with his American girlfriend Chynna Deese near their car. ( Supplied: NSW Police )

At its peak, the investigation included members of the Canadian military, as well as drones, dogs, emergency crews and RCMP major crime units.

Searchers had to contend with difficult terrain and thick forest. Linking arms and traversing ground, as is normally done in search operations, was out of the question, Assistant Commissioner MacLatchy said.

Mr McLeod and Mr Schmegelsky were first reported missing on July 19 after their Dodge pickup truck was found in flames near Dease Lake, British Columbia, 2 kilometres from where a body — later identified as Mr Dyck, 64 — was found.

The RCMP search homed in on the remote community of Gillam in northern Manitoba. ( AP via Royal Canadian Mounted Police )

Days later, the RCMP said the two teenagers were considered suspects in the murders of Ms Deese and Mr Fowler, which took place 500 kilometres away from where Mr Dyck was found, near Liard Hot Spring.

Mr Schmegelsky and Mr McLeod were charged on July 24 with the murder of Mr Dyck.

British Columbia RCMP Assistant Commissioner Kevin Hackett said it would be "extremely difficult" to determine a motive for the three murders.

"Our current belief [is that there] was nothing that links our victims together. There is no indication that this was targeted at this time," he said.

Leonard Dyck was found dead not far from the suspects' burnt-out pickup truck. ( Supplied )

Northern communities across Canada had been on edge as sightings of the two men were reported first in Saskatchewan, and then in Gillam, Manitoba, 3,000km away from the sites of the murders.

"This is like travelling from London to Moscow coupled with the fact that they were travelling in areas that are not highly populated," Assistant Commissioner Hackett said.

Police had said on Tuesday (local time) they were investigating all possibilities including that the suspects might have drowned.

Last month, Mr Schmegelsky's father, Alan Schmegelsky, told Canadian media their son was five when he and his wife had separated.

He said Bryer had a troubled upbringing and was "on a suicide mission".

"They're going out in a blaze of glory — trust me on this," Mr Schmegelsky said at the time.

"Bryer. I love you. I'm so sorry all this had to happen."