A cyclist was attacked and critically injured by a grizzly bear near Big Sky in Montana on Monday.

A man in his 60s was mountain biking alone on a trail on private property in the Spanish Peaks Community near Big Sky, Montana, according to the Billings Gazette.

Montana Fish Wildlife and Parks spokesperson Morgan Jacobsen confirmed that initial investigations revealed the mountain biker probably suprised the bear when he came around a sharp turn on the trail.

"It does not look like a predatory attack," Jacobsen told the Billings Gazette.

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The biker, who escaped the bear and got help from a passing motorist, was airlifted to a Billings hospital and is in critical but stable condition, according to Jacobsen.

Authorities closed the trail while the investigation continues.

Jacobsen encourages people who are hiking, biking or resting in bear territory to make sure they have bear spray, stay in groups and avoid areas with animal carcasses.