Metro tunnel collapse traps workers in S China

Rescuers work at the scene of a cave-in accident in Nanning, capital of south China's Guangxi Zhuang Autonomous Region, Jan. 2, 2013. The tunnel of a metro line under construction in Nanning collapsed Wednesday afternoon, trapping three workers. Two have been rescued and one still trapped.(Xinhua/Huang Xiaobang) .

Two of three workers trapped in a collapsed tunnel of a metro line under construction in the southern Chinese city of Nanning have been rescued.

The accident happened at around 3 p.m. in the tunnel under Minzu Avenue in the capital city of Guangxi Zhuang Autonomous Region. One worker remained trapped

Rescuers said the three workers were working in the tunnel section, where there were two sewage pipelines. The cause of the accident is not immediately known.

The rescue work led by mayor Zhou Hongbo is continuing.