Two construction workers were killed and nine others are still unaccounted for after a flash flood caused by heavy rainfall hit Shenzhen City, South China's Guangdong Province, local authorities said on Friday.

Three incidents of workers being washed away by floodwater were reported to the emergency office on Thursday night in two districts in Shenzhen. One happened in the Futian District and the two others in the Luohu District, where the deaths occurred.

As of 11:00 p.m. BJT on Thursday, a total of six workers have been rescued from the three incidents.

A search and rescue operation is still underway.