CHENGDU - Five people were killed and two others injured in a cable tower collapse on Tuesday afternoon in Southwest China's Sichuan province, work safety authorities said Wednesday.

The accident occurred around 5:50 pm at a construction site of the Tuosan Bridge in Ziyang city, according to sources with the Sichuan provincial bureau of work safety.

The tower used for the bridge's construction collapsed while it was being dismantled, sources said. Five people died on the spot.

The injured have been sent to a local hospital, and they are in non-life-threatening conditions, the sources said.

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