Police following tip that B.C. homicide suspects were seen in York Landing, Man.

Helicopters, a plane, heavily armed officers and police canine units descended on a northern Manitoba community following a tip that two B.C. homicide suspects were spotted in the area.

RCMP posted an update on Twitter late Sunday afternoon saying they were sending resources to York Landing, roughly 90 kilometres from Gillam by air, to investigate a tip that was Bryer Schmegelsky, 18, and 19-year-old Kam McLeod of Port Alberni, B.C., were in the area.

The duo are charged with second-degree murder in the death of University of British Columbia professor Leonard Dyck and are also suspects in the fatal shootings of Australian Lucas Fowler and his American girlfriend Chynna Deese.

A burned-out Toyota RAV4 the teens were travelling in was found near Gillam last week.

James Favel of the Bear Clan Patrol, an Indigenous-led neighbourhood watch group, said it was some of his group's volunteers who reported the sighting to police after they saw two suspicious men while patrolling York Landing on Sunday afternoon.

"These two gentleman matched the description that they were looking for so they immediately called RCMP and alerted them to the presence, and now there is all kinds of things happening over there," Favel, who is the group's executive director, told the Canadian Press in an interview from Winnipeg.

"These two guys definitely stood out."

Favel said the pair bolted as soon as they were spotted.

Despite rumours on social media, Leroy Constant, chief of the York Factory First Nation, posted on Facebook on Sunday evening that no one had been apprehended.

"We are urging everyone to remain indoors with windows and doors locked. Patrols of the community will be done on a 24-hour basis," Constant said.

Mounties issued a tweet requesting that people not disclose officer locations by posting photos of officers in the community to social media.

Savannah Massan, 22, lives near where the two men were possibly spotted. She knew something serious was happening when a local police vehicle started speeding down her street.

"Instantly when you hear the sirens you are going to wonder what's going on because they never turn the sirens on," she said.

"And then everything started to get more, I guess, louder as the helicopter came in and the planes came in."

People are on edge, she added, as they wait for answers and the freedom to move around their community again.

Police said earlier Sunday that they had received more than 200 tips over the course of five days, but none that convinced investigators to believe the pair had left the bug-infested and bog-strewn landscape surrounding the tiny northern Manitoba community of Gillam.

They said it's critical that all Canadians remain vigilant until the duo is apprehended.

Helped by tracking dogs and drones, police went door to door over the weekend, checking every residence and abandoned building in and around Gillam as townsfolk maintained their own stressful vigil for the fugitives.

The aerial search effort got a boost Saturday with the arrival of a Canadian Air Force CC-130H Hercules aircraft equipped with high tech thermal detection gear.

On Twitter, Mounties posted pictures of armed officers checking doors, shining flashlights into garages and cautiously preparing to enter a shed. One picture from the air about 200 kilometres north of Gillam showed a polar bear roaming a grassy shoreline.

Even though police didn't think they'd left the area, they said the possibility remained that the suspects managed to somehow sneak out, or that they'd changed their appearance.

It's all taking a toll on Gillam and several surrounding Indigenous communities, according to one member of the Bear Clan Patrol. Members of the group were invited into the region over the weekend by the Assembly of Manitoba Chiefs to help ease residents' fears.

"Up here, all the towns and communities, they look like ghost towns. Like, everyone's inside. There's a high level of stress, anxiety and fearfulness because they're being kept in their houses," said Wade Taylor, a Bear Clan Patrol volunteer from Winnipeg, who noted the volunteers weren't part of the search effort.

"Quite a few people have even left the area altogether, kind of waiting for this to blow over."

Taylor said almost everyone he talked to shared their thoughts about the search. No one thought the fugitives were in their own community — they believed they were more likely to be in one of the communities nearby, Taylor said.

"Some of the people, you can tell by their voice that they're almost at the point of breaking down crying," Taylor said. "You could say it's traumatic."