Four people died and 12 others are missing after a construction cable broke at around 3am on Friday at a bridge under construction on the Qinghai section of the Sichuan-Qinghai Railway, according to a Qinghai provincial department.

Search and rescue efforts are under way.

The bridge being built over the Yellow River is a steel truss arch construction. Its main span was expected to be closed by the end of this month. (Xinhua)