A scaffolding collapse at one of Beijing's most prestigious high schools on Monday killed 10 construction workers and injured four others, officials said.

The accident occurred at the start of the school day at Tsinghua High School in the city's northwest, but did not affect any classrooms or other buildings used for instruction, according to a statement from the Beijing municipal propaganda bureau. The statement said the injured were in stable condition.

A high school official with the surname Jiang told The Associated Press that all the victims were working to build a school gymnasium at the campus affiliated with one of China's top universities, also called Tsinghua. He said no teachers or students were hurt in the accident.

Relatives of the victims waited outside the school gates to be allowed in. A teary-eyed man said his cousin had been working there and a co-worker at the construction site had called to tell him there had been an accident.

Another relative, Wang Zhiquan, said the accident had claimed the life of his nephew Chen Haijun, a 42-year-old migrant worker from Heilongjiang province in China's northeast.

He told reporters he wanted to see the scene in person and sought proper compensation as Chen was the sole breadwinner for his family, providing for his ill parents and two children.

The official Xinhua News Agency reported that an initial investigation had found that steel bars, used to reinforce concrete structures, had collapsed and caused the accident, citing local authorities. It said police had detained several people responsible, but gave no details about their identity.