A bus explosion that killed eight Vietnamese passengers in Laos on Thursday may have been caused by firecrackers transported in the vehicle, investigators said.
The blast, which also injured three other passengers, occured at 4 a.m. in Khammuane Province, about 8km from the Vietnamese province of Quang Binh.
The joint investigation carried out by authorities of the two countries found burnt firecracker wrappers scattering at the scene.
Investigators said the bus may have been transporting about 200 kg of firecrackers. It's not clear yet how they were ignited.
The vehicle, owned by a Vietnamese company, was carrying 13 people, including 11 passengers, from Laos to Vietnam.
Its driver, Vietnamese national Nguyen Duc Tu, survived the blast and is detained by Lao police for investigation.
A Lao officer checks the bus at the scene of the explosion. Photo: Hue Minh
On Thursday the bodies of all dead victims had been returned to Vietnam.
The bus was destroyed in the blast.
While firecrackers have been banned in Vietnam for 20 years, people in many areas still lit them at traditional festivals and celebrations, which has fueled smuggling from Laos and China