A Florida ambulance driver stopped to check on a fellow motorist involved in a single-car crash - only for the apparently intoxicated man to force his way into the ambulance and drive off, according to authorities.

The victim, a supervisor with the American Medical Rescue private ambulance service, was driving along Interstate 75 near Tampa around 2 a.m. Friday when he spotted the smash-up, according to the Florida Highway Patrol.

The responder - who was driving a Chevy Tahoe clearly marked as a rescue vehicle - rolled down his window to ask the driver of the crashed vehicle if he needed help.

That's when the man - described by the FHP as apparently "under the influence of unknown drugs" - threw himself at the window of the ambulance, forced his way inside, and started fighting with the responder, authorities said.

Fearing for his life, the responder got out of the ambulance and called 911 as the ambulance thief drove off, officials said.

While driving away, the man crashed with a Nissan Altima on an interstate exit ramp, authorities said.

When the Hillsborough County Sheriff's Office responded to that crash, the man fled once again in the ambulance, eventually evading the deputies, officials said.

Within minutes the driver crashed again, this time fleeing on foot, authorities said.

He remained at large on Saturday.

The FHP released dashcam video of the man, asking anyone who recognizes him to get in touch.