A Santa Rosa man suffered a fractured pelvis when he was partially ejected from a car that overturned while his friend, the driver, was spinning doughnuts in a Wikiup parking lot early Thursday morning, the CHP said.

No arrests have been made, but authorities are investigating the case involving driver Steven Molsberry—Colter, 18, the CHP said.

The incident, reported much later, occurred around 12:05 a.m. when Molsberry-Colter and Taylor Martinez-Williamson, 19, were in a Mitsubishi Montero in an unidentified Wikiup parking lot, authorities said.

Molsberry-Colter reportedly lost control of the car while attempting tight circles at a high speed, and the car overturned on its side, the CHP said.

Authorities said he had alcohol in his system but was not legally under the influence.

Martinez-Williamson was partially ejected, though it wasn't immediately clear how seriously injured he was, CHP Officer Jon Sloat said.

Both men live nearby, so Molsberry-Colter walked home to retrieve another vehicle, came back and gave his friend a ride home, Sloat said.

The other man's parents apparently realized some time later that their son had suffered significant injury and called for an ambulance to transport him to a local hospital, Sloat said.

Authorities were alerted, and Sonoma County sheriff's deputies and CHP responded to the scene to investigate the case for potential charges, possibly including reckless driving causing injury, the CHP said.