Federal officials are examining the safety of electric car batteries after a Chevy Volt's lithium-ion battery caught fire.
The National Highway Traffic Safety Administration said Friday the fire occurred in June, several weeks after the car had been crashed-tested at an agency facility.
The agency says officials have concluded the crash damaged the Volt's battery, and the damage later caused the battery to ignite.
Officials don't believe the risk of fire is any greater in electric cars than in cars with gasoline engines.
However, NHTSA says it is working with automakers to reduce fire risk in electric cars and plans further tests.
GM spokesman Greg Martin says the Volt is safe. Chevy is a division of GM.
He says no other fires have been reported among the 5,000 now on the road.