The FBI and the Air Force Office of Special Investigations are investigating the breach of the main gate at Travis Air Force Base in California that ended in a fiery crash and the driver’s death.

In a release Thursday evening, Travis officials said the unidentified driver “gained unauthorized access” to the base through the main gate shortly before 7 p.m. the previous night.

The car crashed shortly afterward and became engulfed in flames, Travis officials said, and the driver was pronounced dead at the scene.

Travis officials said there were no additional fatalities or injuries, and there are no current threats to the base or the community. The investigation is ongoing.

OSI is now working together with the FBI’s Sacramento field office to investigate the incident, the release said.

“The safety and welfare of our airmen, their families and our local community is our top priority,” Col. John Klein, commander of the 60th Air Mobility Wing at Travis, said in the release. “I am extremely proud of how our first responders quickly addressed the situation to keep Travis and the surrounding area out of harm’s way. We are fortunate to have enduring relationships with federal and local law enforcement, and will continue to work hand-in-hand with them through the investigative process.”

The base said that its first responders — including security forces, explosive ordnance disposal technicians and OSI — and emergency officials from nearby Fairfield responded to the scene immediately after the crash.

Travis has not yet commented on how the driver died, what caused the car to erupt in flames, or whether any shots were fired.

Local channel KCRA reported that witnesses said they heard an explosion, and a source told the station that authorities took several propane tanks from the car.

Early Thursday morning, Travis said that travel in and out of the main gate was restricted until further notice, and that the base’s hospital gate was open. Travis said later on Thursday that the main gate is open.

Travis is located near San Francisco, and is the home of the 60th Air Mobility Wing.