The accident occurred at 7:30 a.m. during construction of Shanghai's No. 7 subway, a 33.3-km mass transit line linking the outer Baoshan District with the booming Pudong New District, local police told Xinhua.

The victim suffered fatal head injuries when a cement structure collapsed at the work site on Lingling Road, near the Huangpu River, a witness said.

Police confirmed he was killed instantly and they have launched an investigation.

The accident came a week after a deadly cave-in trapped six workers at a subway construction site in Beijing. Rescuers have recovered five bodies but halted rescue efforts on Monday citing the risk of further cave-ins.