Rescuers transport an injured passenger from a bus after a rear-end collision in Hongcheon, Gangwon Province, Friday. (Yonhap)

More than 70 middle school students on four buses were injured in a rear-end collision as they were returning from a school trip in Gangwon Province on Friday, according to reports.

After the accident, those who sustained serious injuries were taken to nearby hospitals.

The buses were involved in a collision with three trucks and a sedan on an interchange in Hongcheon, Gangwon Province, police said.

The police said the driver of one of the school buses was falling asleep while driving.