Hundreds of construction workers in Shenzhen have clashed with government officials sent to demolish their temporary dormitory. About 500 workers attacked the officials with bricks and clubs on Thursday. Fourteen of the officials were injured, six seriously enough to be admitted to hospital. One was in a coma yesterday. A policeman from Zhaoshan District Public Security Bureau said about 20 people had been detained, including the person in charge of the construction site. The temporary dormitory was built by Shekou Chunzhu Construction for 1,000 workers it employed to build an industrial park. The urban planning authority ordered the company to demolish the building in March after its land usage permit expired. The firm ignored several demolition notices, Shenzhen Special Zone Daily reported. Finally, on Thursday, dozens of officers and three bulldozers were sent to pull down the structure. 'At first all went well. Some workers obeyed the order and started to move out. The officers successfully pulled down part of the building,' a police officer said yesterday. But he said the person in charge of the construction site refused to let the officers continue. The two sides then began to bicker. The officers were surrounded by angry workers, who pelted them with bricks and clubbed them. The three bulldozers were also damaged, the police said. More police later arrived and dispersed the crowd. Local media reports said the Nanshan district government had ordered the demolition to continue, but promised to relocate the workers to another dormitory. Shenzhen has launched a crackdown on illegal buildings this year as part of the government's campaign to improve the city's environment. In the Nanshan district alone, 40 illegal shopping malls have been flattened this year, Shenzhen Evening News reported yesterday. It said officers in the neighbouring district of Lowu had cleared 554,000 square metres of illegal structures.