SORIA, Spain (AP) _ A bus carrying teen-agers to a summer camp crashed head-on Thursday with a truck that crossed into its lane, killing at least 25 passengers and both drivers, officials said. More than a dozen others were injured, several critically.

The students, from two religious schools just outside Barcelona, were nearing their destination when the accident occurred on a hill near Soria, about 125 miles northeast of the capital, Madrid.

Bodies of the victims were strewn across the road and in a steep ditch where the bus had flipped, the officials said. The front end of the bus was mangled in the collision and its seats scattered around.

It wasn't immediately known what caused the truck, which was hauling pigs, to cross over into the oncoming lane of traffic.

Juan Jose Lucas, president of the regional government of Castile and Leon, described the scene as ``horrendous.''

``It's a day of tremendous pain, especially when it deals with young people who were going on holidays,'' he said.

Rescue workers collected the bodies in wooden coffins and brought them to a sports complex in Soria, where parents will identify them on Friday.

Weeping relatives seeking information about their children gathered at the schools, where they were met by psychologists, religious leaders and local politicians looking to try to console them.

Many of the parents at Modolell de Viladecans were not told whether their children were among the survivors or not as they left Barcelona for Soria. Those who could not drive themselves were taken on buses for the six-hour ride.

A social worker who went on one of the buses and who identified herself by her first name, Montse, said, ``The parents don't know whether their children are dead or alive. We want to make the trip with hope... The worse ride will be when they come back with the bodies.''

King Juan Carlos and Queen Sofia expressed their ``profound sadness'' to the crash victims' families, and French President Jacques Chirac also sent his condolences.