A train carrying solid rocket booster parts for NASA's space shuttle program derailed in Alabama, injuring six people, but none of the material spilled, officials said.

"There was a train wreck, six injuries," a spokesman for the Alabama Emergency Management Agency said.

The National Aeronautics and Space Administration (NASA) said the train was carrying parts for the solid fuel rocket boosters used in space shuttles.

NASA spokesman Allard Beutel said the train was traveling from Utah, where the segments are manufactured, to the Kennedy Space Center in Florida where the space shuttles are launched.

He said the parts were destined for shuttles to be launched in October and December.

Twin solid rocket boosters are used to give most of a space shuttles thrust on liftoff. The solid fuel they use is very stable and has a high ignition point.

Alabama media said the train derailed in a swampy area after a bridge tressel collapsed.