Two men were killed and six others were injured in Shanghai yesterday in two separate incidents at subway construction sites.

The operator of a crane was crushed to death when his 50-ton machine toppled over at the site of the Xiaonanmen station on Metro Line 9.

Smoke billows from the subway construction site in Shanghai yesterday, where one man was killed and six others were injured. [China Daily]

In the second incident, a man was killed and six were injured when a fire broke out underground at the site of Metro Line 11.

"The fire started at the underground level of the station at the intersection of Caoyang Road and Baiyu Road," a witness surnamed Ji said.

"Then, a pall of smoke hung over the air.

"Firemen rushed to the site, but the fire was blazing fiercely by that time. The flames would have reached as high as a five-story building," Ji said.

The fire took four hours to be brought under control, and an investigation by the local safety supervision department showed it was started when a supply of acetylene ignited.

The injured suffered burns to between 5 and 10 percent of their bodies, a source from Ruijin Hospital said.

They also suffered the effects of smoke inhalation, and three of them needed tracheotomies, doctors said.

The injured men are all from Anhui province and planned to return to their hometowns for Spring Festival today, local media said without elaborating.