Seven people were killed and one person injured when a minibus collided with a heavy truck on a highway in north China's Inner Mongolia Autonomous Region Monday morning, police said.

The head-on collision happened at 6:50 a.m. on the outer ring road of Baotou City.

The identities of the six men and one women killed were not immediately known. The woman who survived the accident was seriously injured. The truck driver was unharmed.

The cause of the accident is under investigation.