SAN FRANCISCO -- Police said on Thursday they are investigating a single-vehicle car crash that occurred late Wednesday in Pleasanton, US state of California.

The accident "resulted in multiple fatalities," the police said in a statement, adding that they are conducting a thorough investigation but do not have additional information at this point.

The number of people killed or injured was not immediately available, nor was the cause of the crash.

"For now, our priority is protecting the victims' identities as we notify family and complete our investigation," the police said.