Car in U.S. Air Force base crash was loaded with propane tanks: source

LOS ANGELES (Reuters) - A car that breached the main gate to Travis Air Force Base in northern California and burst into flames earlier this week was carrying a cargo of propane tanks that the driver apparently ignited himself, a law enforcement official familiar with the case said on Friday.

The driver, who has not been publicly identified, died at the scene, about 50 miles (80 km) northeast of San Francisco, on Wednesday. No one else was hurt, the base said in a statement.

Investigators believe the driver, determined to be a local resident, deliberately set off the blast as he drove through the base entrance, according to the law enforcement source, who spoke on condition of anonymity because he was not authorized to discuss the probe.

Air Force officials previously said the car crashed shortly after entering the base and became engulfed in flames, but gave no explanation for the origin of the fire.

The law enforcement official said that no shots were fired by guards or base personnel during the incident.

There was no immediate evidence the driver was motivated by extremist ideology, the source said, but investigators were looking at both that possibility and whether a personal grievance was involved. The official declined to say whether the man had any connections to the base.

The Federal Bureau of Investigation planned to hold a news conference later on Friday to discuss the case. Gina Swankie, a spokeswoman in the FBI's Sacramento field office, declined to provide any details.

Travis Air Force Base, celebrating its 75th anniversary this year, occupies nearly 6,400 acres east of Fairfield, California, with a total military and civilian workforce of 14,350.

The base is home to the largest airlift organization in the Air Force, with a fleet of C-5 Galaxy and C-17 Globemaster III cargo planes and KC-10 Extender refueling aircraft.

(Reporting by Jonathan Allen in New York and Mark Hosenball in Washington; Additional reporting and writing by Steve Gorman in Los Angeles; editing by Jeffrey Benkoe and Leslie Adler)