At least three people died at the scene and one was injured after a 36-seat passenger coach carrying 18 people veered off National Highway 6 and crashed into a drainage ditch in Chieng Hac Commune, Son La Province, early on Saturday.
Initial reports said the accident occurred at about 4.15 am when the coach, driven by Nguyen Van Huong, 43, was travelling from Hanoi towards Son La. The vehicle plunged into a drainage ditch on the right side of the road and overturned.
At the time of the crash, there were 18 people on board, including 14 passengers, two drivers and two assistants.
The crash killed three people instantly, while one injured person was taken to a local hospital for emergency treatment.
At the scene, the coach smashed through a section of bridge guardrail before overturning on its side.
Authorities said it was raining at the time of the accident, with fog and slippery road conditions. Preliminary checks showed that neither driver had alcohol or drugs in their system.
Son La police are investigating the cause of the crash.
