The rescue of the Beijing subway collapse is under way on Thursday, March 29, 2007. [photobase.cn]

The three bodies were all heavily pressed upon by collapsed concrete and meanwhile, the space beneath the ground which rescuers can move about is very narrow. Therefore, it is difficult to pull the bodies out.

In addition, collapse may occur anytime in the tunnel, rescuers said.

Earlier report said the collapsed section of the tunnel covers an area of about 20 square meters and is about 11 meters underground.

Rescuers and more than 10 experts have met many times to study different rescue plans.

At the same time, rescuers are still searching for the remaining two workers, who have been feared dead.

The collapse happened at 9:30 a.m. on Wednesday at a construction site for the No.10 Subway Line in Haidian Nanlu Road between the third and fourth northern ring roads in the city's Haidian District.

Six workers were buried underground after the accident, of whom one came from central China's Henan Province and the other five from southwestern Sichuan Province.

Rescuers recovered a worker's body Friday afternoon after more than 50 hours of excavation. The victim was confirmed to be 20-year-old Li Peng from Henan.

Family members of the six workers are in Beijing now to handle the aftermath.

Local police have detained 10 people over the subway cave-in, including the work supervisor and tunnel designers but the labor contractor, Zhou Yongfu, is reported to have fled.

The construction company - China Railway 12th Bureau Group Co.- refused to report the accident to municipal authorities when the collapse occurred, instead mounting its own operation to rescue the trapped workers.

In an attempted cover-up, project managers ordered all the workers to stay at the construction site and told them not to talk to media and police. They confiscated mobile phones from workers.

The Beijing municipal authority finally learned of the accident at 5:00 p.m. on Wednesday, almost eight hours after the collapse occurred, after a worker from Henan called Henan police.

Municipal government officials told Xinhua on Friday that rescue work had been delayed by the company's cover-up attempts and the complicated underground conditions.