HEFEI - A malfunctioning elevator plunged from the 18th floor, crushing four workers to death and seriously injuring another at a construction site in East China's?Anhui province, local firefighters said on Saturday.

The empty elevator suddenly plunged at about 4:30 pm Friday as it was ascending to the 18th floor of a building under construction in Guichi district in the city of Chizhou.

One worker died at the scene. The other four were rushed to the local hospital where three died on Friday.

The other worker remained in critical condition as of Saturday afternoon.

In wake of the accident, the municipal government has ordered all construction sites in the city to suspend work. The cause of the accident is under investigation.