VANDENBERG AIR FORCE BASE, Calif. — The Latest on a wildfire at a California military base (all times local):

10:45 a.m.

Authorities say a firefighter assigned to a blaze at a California military base was killed and another was seriously hurt when a water tanker truck overturned on a highway.

Ventura County Fire Department spokesman Steve Swindle says the crash occurred Wednesday at a roundabout on State Route 246 just outside Vandenberg Air Force Base.

Swindle says Fire Engineer Ryan Osler died and the other firefighter was hospitalized in serious condition. They were the only occupants of the truck.

The California Highway Patrol is investigating the crash.

Swindle says Osler was in his 30s and a second-generation firefighter.

Ventura County is among several departments that have sent crews to the 19-square-mile fire at Vandenberg. The fire broke out Sunday and was 45 percent contained. No structures were threatened.

9 a.m.

Crews are gaining ground against a wildfire at a central California military base burning near launch pads used to send satellites into space.

Firefighters at Vandenberg Air Force Base are focusing Wednesday on the blaze’s southeast boundary after it grew to more than 19 square miles. It is 45 percent contained.

Voluntary evacuation orders are in place for about 400 residents of the San Miguelito Canyon area just off the base near Lompoc.

There is no word of any structures threatened on the sprawling base, much of which is undeveloped and rugged mountain land.

More than 1,000 firefighters are fighting the flames that broke out Sunday in a remote canyon. The cause is under investigation.

Officials say there is no immediate threat to the space launch complex.