A kite surfer in San Francisco was blown from the ocean onto a busy coastal thoroughfare and struck by a car Friday, police said.

The incident was reported at 3:12 p.m. at the intersection of the Great Highway and Sloat Boulevard near the zoo, according to the San Francisco Police Department.

Police said the surfer was setting up his board when a gust of wind, which reached 42 miles per hour, lifted and deposited him in the highway's southbound lane where he was hit by a car.

But a witness told NBC Bay Area that the man was in the ocean and carried nearly 50 feet over sand dunes and parking spaces into the path of oncoming traffic. The surfer was caught in an uncontrolled spiral and unable to safely eject, he said.

The victim was transported to San Francisco General Hospital with life-threatening injuries, police said, stressing that this is not a hit-and-run collision.

Police, who deemed the accident bizarre, temporarily closed the Great Highway's southbound lanes near Lincoln Way during the investigation. They were reopened around 5:30 p.m., officials said.

Anyone with information about the incident is asked to contact the SFPD anonymous tip line at 415-575-4444 or text a tip to TIP411 with SFPD at the beginning of the message.