XINING - Seven people died and 12 others were injured when a heavy truck collided with a pick-up truck head-on early Tuesday in Northwest China's Qinghai province.

The accident happened at 4 am when the two vehicles crashed near Da Qaidam township, Haixi Mongol-Tibetan autonomous prefecture, on National Highway No 315 which runs from the provincial capital Xining to Kashgar of Xinjiang Uygur autonomous region, according to a traffic police officer under the provincial public security department.

When the accident happened, four people were in the cab of the large truck and the pick-up was carrying 18 people, with five in the crew cab and 13 others on the truck bed, said the police officer.

Seven people died at the scene, and the 12 seriously injured people were rushed to hospital, he said.

Further information was not known yet, and the cause of the accident is under investigation.