LANZHOU, July 11 -- Four villagers were killed and another four injured after a tricycle they took collided with a truck in northwest China's Gansu Province on Friday evening, local authorities said Saturday.

The accident happened at about 6:30 p.m. in Qinzhou District, Tianshui City when the eight villagers on the unlicensed tricycle were back from a sightseeing trip in Longnan City.

Four died at the scene and another four are receiving treatment at a local hospital.

The cause of the accident is being investigated.