The incident occured when the arm of the 1,000-ton crane, toppled and fell down suddenly in a trial operation to lift a wind turbine.
Five people were killed after being crushed beneath the crane. They included Yu Yongdong, Chinese Communist Party secretary of the Jiuquan industrial park (the main official for the industrial park), Jia Ping, director of the Jiuquan Industrial Park management committee, and Liang Feiyan, deputy director of Jiuquan municipal archives bureau (and Yu's wife). Two Sinovel workers were also killed.
According to witnesses, when the crawler crane started to lift the load hook for a static test it showed a weight of 318 tons, 42 tons less than the limit. Soon after the load was put at 100-centimetres and the crane jib broke off at the base causing it to fall.
The crane belonged to Ningxia Tianxin Construction Development.
The accident, in Jiuquan, northwest China's Gansu province, took place at about 11 pm, said Zhan Shunzhou, vice-mayor of Jiuquan. An investigation into the cause of the accident is underway.
This is the second major accident this year involving a Sinovel turbine. In January, three workers were killed while nstalling and testing a Sinovel wind turbine in Shangyi County, in China's northern Hebei province.