CHENGDU, March 30 -- Five people were killed Thursday after a heavy-duty truck collided with a car at the exit of a tunnel in southwest China's Sichuan Province, local police said.

The accident occurred at about 9 a.m. in front of a tunnel leading to a hydropower station at Xiluodu in Pingshan County.

Two people were killed at the site. One died en route to the hospital and the other two died after emergency treatment failed.

An investigation into the cause of the accident is under way.