CHINA has systematically covered up the accidental deaths of at least 10 workers, and perhaps many more, in a rush to construct the futuristic ”bird’s nest” stadium in Beijing for this summer’s Olympic Games.

The estimates are drawn from dozens of interviews conducted over six months, under a guarantee of anonymity, with employees from the huge building site in a northern district of the capital.

Witnesses have told The Sunday Times of seeing workers plummet to their deaths from the perilous heights of the stadium, which was designed by a consortium including Arup, the British engineering firm, and Herzog & de Meuron, the Swiss architects.

The bodies were swiftly removed by police, who sealed off accident scenes with orange tape and cleared other workers from the area while the dead were loaded into police vehicles, witnesses said.

Managers and police ordered the workers not to mention the deaths to anyone and not to talk about the accidents among themselves.

Gordon Brown heaped praise on the stadium after a visit yesterday, calling it “a huge effort by the people of Beijing, a huge contribution by China to world peace and prosperity”.

Chinese officials deny that there have been any deaths. The authorities have ensured the silence of bereaved relatives by making unusually high compensation payments, which some workers say can amount to up to £13,000. By contrast, labourers on the site said they earned £3 a day and skilled welders earned £4.40 a day.

The conservative estimate of 10 accidental deaths since construction began on the stadium in 2003 was reached by comparing numerous accounts from witnesses who worked at the site at different periods.

It does not include any deaths at other Olympic venues under construction in Beijing and across China as the nation enters a final frenzy of preparation for a mass celebration of patriotism and Communist party propaganda.

The overall Chinese death toll may never be known. Five workers were said to have died during the building of the Olympic stadium for the 2004 Games in Athens. There was only one accidental death connected to the Sydney Olympics of 2000, and one welder was killed at the stadium built for the 1996 Games in Atlanta.

Several factors appear to have contributed to the Beijing stadium death toll. The sheer ambition of Herzog & de Meuron’s design has required workers to spend long periods at great heights to weld and join the struts and girders that are interwoven to form a bowl shaped like a bird’s nest.

Arup said: “Sadly, fatalities during construction could be due to many different things that have nothing to do with design.”

Most of the workers employed on the project are poorly educated migrant labourers from the inland provinces of China, who have scant specialist training and no experience of building on such a gigantic scale.

Of all their accounts, none was more telling than that of a 25-year-old construction worker from Gansu province who worked as a welder at the site for more than a year. He spoke to The Sunday Times last summer, early in the investigation.

“One day towards the end of [2006], the weather was terribly cold. On the top of the ‘bird’s nest’ I could see some ice. I stood on the ground, thinking of how best to climb to the top to get on with the welding,” he said.

“Just at that moment I heard a terrible scream. Before I realised what had happened I heard a thump on the ground. I suddenly realised that someone had fallen from the top of the nest - yet I couldn’t see anybody on our sandpile, which was heaped in the middle of the running track.

“The manager ordered workers to excavate the sand with shovels. After half an hour a dead body was pulled out of the heap. The body was gory and I didn’t dare look at it.

“The body was taken away immediately and everyone on the spot was told to keep it secret. For a couple of nights after that I had nightmares. In the end I quit and went back to my home town.

“So why did I come back again? Because I couldn’t find a better job. And I guess because my girlfriend broke up with me. I felt lost. So I came back here to forget my unhappiness through hard work.”

As the Chinese leaders urged the project on to completion last summer, the casualties continued in and around the “bird’s nest”.

One migrant worker from Pingyin county, in northeast China’s Shandong province, described how he saw a work-mate die in front of him.

“He slipped off the boards, the safety rope broke, he fell 30 yards to the ground from the scaffolding and died,” the worker said.

“He was only 33 years old and had a pretty young wife and a lovely son. I saw her when she came to get his things and collect his body.

“I felt such pity for him. Just 33. His life was just beginning and then it was over. People said his wife got more than 200,000 yuan [£13,000]. We don’t know exactly because the negotiations were secret. At least his wife and son were lucky.”

Some of the deaths appear to have been bad luck. One employee, who worked on the site for three years, described the fate of a worn-out migrant worker who decided to sleep overnight on the ground inside the stadium.

When a bulldozer drove into the arena before first light, it ran over him. The driver was so stunned that in his confusion he reversed the vehicle and its tracks crushed the victim for a second time.

In interviews workers talked of the relentless pressure to get the job done, of abusive subcontractors who frequently withheld pay in violation of China’s labour laws and of harsh restrictions on their personal lives in thin-walled dormitories where men bunked 12 to a room.

One problem cited again and again was the use of subcontractors - a practice that, Chinese critics allege, leads to opportunities for corruption.

The lead contractor on the stadium is the state-owned Beijing Urban Construction Group. There appear to be up to five levels of subcontractors on some jobs.

Several workers said the subcontractors tried to conceal workplace injuries from the authorities.

“Some bosses do not report accidents to the lead contractor and the Olympic construction committee,” a safety inspector said in an interview.

“They know that if the lead contractor knows which construction firm has a bad record of deaths and injuries, the company could be punished and may not be given more projects.”

Complaints about delayed wages were persistent. One man, who said he knew he was talking to a reporter, handed over an open letter addressed to the Chinese government. It read: “At the beginning I was happy to work in the ‘bird’s nest’ because I was making a contribution to the Olympic Games, but now I am very angry.

“Why? The contractor has defaulted on my salary for half a month. My family is anxious. My two children need money to pay tuition. My wife needs money to buy fertiliser. My old parents need money to go to hospital.

“I can’t understand it. The Olympic stadium is a big state project. To my contractor this amount of money is nothing, but for me it is a lifeline. I hope the government can pay attention to this issue.” In the worker’s own interests, the letter was not delivered.

For the younger men sitting around inside a dormitory, the exhaustion of sleep comes as a relief from loneliness and frustration. “The lack of women is a big problem,” said a worker named Qi. “Most of us haven’t been home to sleep with our wives for six months or a year. The single men have no chance or time to talk love with girls.”

His friend Huang, 25, boasted: “I go to the barber’s shop very often and I know how to bargain with the prostitutes. Sometimes I get a discount from 200 yuan (£13) to 50 yuan.” All the young men laughed at him, shouting: “You cheapskate!”

They get by, like many Chinese workers, on a mixture of pride, fatalism and necessity. But that does not mean they are ignorant.

“We know that builders died in Greece at the Olympic site,” said one young labourer. “At first the government denied it but after the opposition party and workers’ union disclosed the names of the dead the government had to admit it.

“But in China who dares to investigate such a sensitive issue? Would you dare?”

No one was available for comment at the Beijing 2008 Olympic organising committee.

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