The crash happened around 8:15 a.m. in Sandy Township on Bee Line Highway at Sher de Lin Road.

Officials at the scene said 42 students were on board the DuBois Area School District bus.

The district's transportation director said the students were part of an eight-bus caravan on their way to a field trip at the Camp Mountain Run Boy Scout Camp. The bus was heading north at the time of the crash.

In addition to the three students, a school bus driver and chaperone were injured. Officials said the driver of a maroon-colored car was severely injured and was airlifted to a hospital. Crews had to cut the roof off the car to free the driver. The driver of a third vehicle -- a truck that was also involved in the crash -- suffered minor injuries.

Police would not comment on the severity of the injuries of those on the school bus. All of the passengers on the bus were taken to DuBois Regional Medical Center to be checked.

Police said the driver of the car drifted over the center line of Route 255, slamming into the pickup truck before striking the front of the school bus. The impact with the bus was so hard it knocked the front wheels off the bus.

Police said the crash was one of several bus accidents they've responded to in the last couple of years.

"Initially, when you get on scene, it's total chaos. This bus had more than 40 kids on it along with chaperones, so initially it takes a lot of teamwork from (multiple) agencies," said Sandy Township police Sgt. Rod Fairman.