This military flare canister was found on the shore of Marsh Lake over the weekend. (RCMP)

Yukon RCMP are warning people near Marsh Lake to watch out for potentially hazardous military flares in the area, after one of them was found over the weekend.

The Canadian Forces deployed a total of 18 white phosphorus flares in the Whitehorse area as part of a national search and rescue exercise last week.

But over the weekend, a Marsh Lake resident found the canister from one of the flares about three metres from shore. The resident called police upon seeing the canister was labelled as "dangerous material."

"That object turned out to be a deployed flare from the recent search and rescue military exercise," Sgt. Don Rogers told CBC News on Monday.

The RCMP's explosives disposal unit was brought in to Marsh Lake and safely disposed of the flare.

Should have sunk

Rogers said the discovered flare is believed to have deployed properly, but it did not fill up with water and sink as it was designed to do.

White phosphorus can cause intense burns if someone comes into contact with it.

One of the 18 flares that were used last week did not deploy according to plan. That flare has not been found, which has prompted RCMP and military officials to issue a public warning.

"The Canadian Forces are presently coordinating between Joint Task Force north and the local RCMP to have [an] explosive ordinance disposal team come back and retrieve canisters that have been left behind us," said Capt. Alexandre Cadieux, who was involved in the military exercise.

Cadieux said he hopes the flare that did not deploy properly will be found by the military team.

He could not say if the Canadian Forces had informed local authorities about the potential hazards before leaving the territory last week.

Police describe the aluminum canisters as being about 30 centimetres long and over six centimetres in diameter.

Both the military and RCMP warn people in the Marsh Lake area that if they find any flare canisters, they should stay away from them and call the police immediately.