(adds day accident occurred to lead)
Nine people were killed and 21 others injured in a bus accident Monday on a highway in Tornadizos, a town in the north-central Spanish province of Avila, the Civil Guard said.
All of the injured people are listed in serious condition, General Traffic Administration, or DGT, officials said, adding that the accident occurred when the bus veered out of its lane.
Police are searching the area for additional victims since several of the passengers were thrown from the bus.
Some people may still be trapped in the wreckage, Civil Guard spokesmen told Efe.
The bus, which did not tip over completely, was about 75 percent full at the time of the accident, passengers told Efe. EFE