Toronto -- Canadian police said they will conduct a door-to-door canvas in two communities in Manitoba over the next three days while pressing the search for two suspects in the slaying of an American woman, her Australian boyfriend and another man. But authorities also urged "all Canadians" to be on the lookout for 19-year-old Kam McLeod and 18-year-old Bryer Schmegelsky.

Police also released surveillance video of McLeod and Schmegelsky as they walked through a store last Sunday in the neighboring province of Saskatchewan. Schmegelsky is dressed in army fatigues.

Royal Canadian Mounted Police Cpl. Julie Courchaine said officials were "open to the possibility" that the two suspects could have had assistance in leaving the Gillam and Fox Lake area of Manitoba.

Courchaine also said they may have altered their appearance and someone could have inadvertently given them assistance in leaving the area. No cars have been reported stolen.

"It is possible that someone may not have been aware of who they were providing assistance to, and may now be hesitant to come forward," she said at a police update in Winnipeg, Manitoba.

Canadian Public Safety Minister Ralph Goodale said the military had been called in to give police air support during their hunt for the young men.

Gillam is more than 2,000 miles from northern British Columbia, where the three people were found slain in two places last week. The victims have been identified as American Chynna Deese, 24, Australian Lucas Fowler, 23, and Leonard Dyck, 64, of Vancouver.

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