By VnExpress  September 15, 2018 | 12:36 pm GMT+7 Medical personnel and police forces rush to the accident site to carry out rescue operation. Photo by VnExpress/Duc Quan 12 people died and three others were severely injured as a heavy crash sent both vehicles to plunge down a stream along the road in Lai Chau Saturday. The accident occurred at 10 a.m. on National Highway 4D in Tam Duong District in Lai Chau Province, around 400 kilometers to the southeast of Hanoi, when the tank truck hit the back of a minibus while driving down a slope. Both vehicles were thrown into a stream six meters down the road. 11 people were killed on the spot and a child died on the way to the hospital. Three others sustained major injuries and are being taken to local hospital for treatment, said Giang A Tinh, vice chairman of Lai Chau. The driver of the minibus, which had 14 people aboard, was among the dead, local media reported. Medical personnel and police forces were rushed to the accident to carry out rescue operation. The cause of the accident is under investigation. Road crashes are a leading cause of deaths in Vietnam, killing almost one person every hour. Last July, another severe crash was reported in the central province of Quang Nam when a container truck collided with a minibus heading for a wedding ceremony, killing 13 people including the groom.