Police say U.S. Secretary of Commerce John Bryson is being investigated for two hit-and-run car crashes near the city of Los Angeles on June 9.
Police said Bryson struck the rear end of a vehicle that had stopped for a passing train. He then spoke briefly with the occupants and left the scene, apparently hitting the car again as he did so.
Police said five minutes later Bryson struck another vehicle nearby.
Police found him unconscious behind the wheel of his car.
A spokeswoman for the Commerce Department said Bryson suffered a "seizure." Spokeswoman Jennifer Friedman said in a statement that Bryson was hospitalized in California but has returned to Washington.
The passengers in the other cars reportedly had no serious injuries.
Police said there was no initial indication of alcohol or drug use and that no formal charges have been filed yet.
Based on reporting by AP, AFP, and Reuters