March 23 (UPI) -- The FBI and the U.S. Air Force are jointly investigating the crash and burning of an unauthorized vehicle at California's Travis Air Force Base.
The vehicle gained access to the base through the main gate on Wednesday evening, then crashed and caught fire, a base statement said. It added that first responders, including ordnance disposal teams, arrived to put out the blaze.
"The driver of the vehicle was pronounced dead at the scene," the statement read. "There were no additional injuries."
An unidentified official at the base said the vehicle appeared to contain propane tanks. The driver was a civilian, and no shots were fired at the vehicle, the official added.
The Air Force added that there are no current known threats to the Travis base or the surrounding population in Solano County, Calif., near San Francisco.
Investigators are considering a variety of motives for the incident, including whether it was a possible terrorist attack or suicide, ABC News reported.