MINNEAPOLIS (WCCO) – A 28-year-old Barnum, Minnesota, man is in critical condition after his car crashed into a tree in Carlton County.

First responders found the man unconscious and not breathing in his 2004 Hyundai Elantra shortly after 1 a.m. Monday. CPR was started at the scene, and he was taken to Mercy Hospital in Moose Lake and later airlifted to Essentia Health in Duluth.

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The man, who was not wearing a seat belt, is believed to have hit a deer a few minutes before the collision.

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Speed was an issue and a medical factor may have also been at play, the Carlton County Sheriff’s Office said.

The Carlton County Sheriff’s Office,Minnesota State Patrol, Blackhoof Fire Department, Carlton Ambulance, Mercy Ambulance Advanced Life Support, and Life Link III Air Ambulance assisted at the scene.

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The man’s current condition is unclear.