More than 100 piglets died after an accident in southeast Nebraska sent the livestock trailer they were riding in awry.

But Jefferson County Sheriff Nels Sorensen says about 670 other piglets in the trailer survived the accident and were able to be transferred to other vehicles.

The accident happened Tuesday on state highway 15, about nine miles north of Fairbury.

Officials believe the driver of the truck fell asleep and started to drive into a roadside ditch. When the driver tried to steer back on the road, the trailer detached and overturned on the highway.

The truck struck a mailbox before stopping. The driver and passenger were not injured.

Neighbors and rescue workers helped transfer the piglets to other vehicles.

Copyright 2010 The Associated Press.