Rescuers work at the collapsed road where a subway tunnel was under construction in Hangzhou, capital of east China's Zhejiang Province, yesterday. At least one person is dead and 16 are missing and 13 vehicles were also trapped after the road caved in on a subway tunnel under construction in Hangzhou yesterday. -Xinhua

At least one person is dead and 18 are missing after a road caved in on a subway tunnel under construction in the eastern Chinese city of Hangzhou yesterday, rescuers said.

Nineteen people were taken to hospital, said a spokesman with the rescue headquarters.

An investigation team was set up soon after the accident, involving authorities of work safety, construction, supervision and public security, he said.

Witnesses and rescuers earlier said at least 50 people were trapped underground, but the exact number is still unknown. They are believed to be mostly construction workers.

Eleven vehicles were also trapped in a 75-meter-long, 15-meter-deep crater after a section of road collapsed into the tunnel in Hangzhou, capital of Zhejiang Province, at about 3:20 p.m..

The subway is being built on the Fengqing Avenue in Xiaoshan District in the southeastern part of the city.

Provincial governor Lu Zushan, who is overseeing the rescue operation at the site, ordered rescuers to soon find out the exact number of trapped people and medical workers to spare no efforts to save the injured.

He also ordered a suspension of subway construction on all lines.

Construction workers who survived the accident were still in horror when seen Saturday night at the Xiaoshan Traditional Chinese Medicine Hospital.

"There is some distance between where I was working and the cave-in site. Lots of workers immediately rushed to the hoist to be lifted above ground. The height is about 10 meters," said Zhu Juzhong, a 56-year-old worker from the southwestern Sichuan Province.

"Some colleagues who moved slowly were buried," he said.

About 30 workers managed to escape on the hoist, and three fell from the hoist during the rush, he added.

Zhu suffered slight injuries and is in stable condition.

Xu Weixi, 43, from Hangzhou's Chun'an County, said the hoist had reached a very high level when he rushed there.

"I grasped a steel cable and climbed up desperately," he said.

Xu suffered contusion of kidney and is also in stable condition.

Thirteen people were hospitalized in the Xiaoshan hospital, and four of them had left, said Shi Jianfang, director of the emergency treatment department.

"Three of them suffered bone fractures and they are now on stable condition. Only one person was injured seriously in the chest, and he is still in danger," Shi said.

"We will do our best to save his life, so long there is a beam of hope," he said.

Among the trapped vehicles in the crater, 27 people traveling on a bus escaped after the driver opened the door, witnesses said.

Water from a river flowing beside the cave-in site soon seeped into the tunnel. Its depth is estimated at about four or five meters and rising.

Five frogmen are searching for people trapped in the vehicles.

About 2,000 rescuers are struggling to pump water out of the tunnel and haul the vehicles from the crater.

Local authorities have cut off power and water supplies to this area to ensure a safe and smooth rescue operation. The subway company also dispatched about 100 technical staff to the site.

Eight vehicles had been pulled out by 11:00 p.m.

Construction of the first phase of Hangzhou's subway network was launched in late March last year, comprising sections of the No.1, No.2 and No.4 lines. The accident site is part of the No. 1 line.

The project will extend 68.79 kilometers from the city's northeast to the south at a total cost of 34.936 billion yuan (5.1billion U.S. dollars) upon completion in 2011.

A 47.97-km section of the No.1 subway line is being built as part of the project.

Hangzhou plans to establish eight subway lines with a total length of 278 kilometers by 2050, involving 100 billion yuan in investment.