Six people were killed and 13 injured in a road accident that occurred Monday morning in southwest China's Guizhou province, local authorities said.

At 9:38 a.m. Monday, a bus traveling from Qianxi county to the city of Guiyang crashed into a highway guard rail, tumbling down a 30-meter-deep ditch, according to the emergency office of Guiyang.

The injured have been taken to a local hospital for treatment.

The cause of the accident is under investigation.