Eluding a border posse near Waterton park has left a pair of suspected illegal immigrants between burning timber and a grizzly bear.

On Tuesday night, RCMP apprehended two Hispanic men running along Hwy. 6 on the Canadian side of the border near the Chief Mountain Crossing, 200 km southwest of Calgary.

Another man was apprehended in shrubbery nearby, but two other males escaped.

While they may have retained their freedom, RCMP Cpl. Al Fraser said the duo may have fled into the clutches of a grizzly bear spotted in an area that's also menaced by a forest fire.

Fraser said the fire could even put the fugitives in the path of a larger stampede.

"When you've got a fire like that, you've got all kinds of animals getting out of the way -- there could be a black bear and a cougar," said Fraser.

"It can be a little traumatic."

The pair's perilous flight has kicked up a swarm of searchers, including an RCMP helicopter, a police canine unit, U.S. Homeland Security, Blood Tribe Police, Parks Canada officials and border agents from both nations.

"It's not just that they're illegal immigrants, we want to make sure they're safe, watered and fed and we can deal with the rest of it later," said Fraser, adding it's possible the men fled back to the U.S.