KUNSHAN, China - A massive explosion killed 69 people Saturday as it ripped through a factory in eastern China, officials said, as badly burned victims were rushed to local hospitals. The blast in Kunshan, a city in coastal Jiangsu province near Shanghai, also injured 187, in what appeared to be an industrial accident, state-broadcaster China Central Television (CCTV) reported. Photos taken shortly after the explosion show victims with their clothes burned off lying on the ground outside the white factory complex which was billowing black smoke.State media said the plant produced car parts for automotive companies, including US giant General Motors. A worker at a neighbouring Japanese owned factory told AFP he had seen dead and injured victims covered in brownish dust after the explosion. ‘Their skin was broken. It was gone,’ he said.An AFP reporter at the scene saw a badly burned body on a stretcher being wheeled by hospital staff. The explosion began in a wheel hub polishing workshop, the official Xinhua news agency said. Preliminary investigations show that the blast was caused by dust produced as workers polished metal meeting with high temperatures or an open flame, the ministry of public security said on a verified microblogging account.‘We heard the explosion and we were all shocked,’ a security guard from a nearby factory who declined to be named told AFP. He said the blast occurred as workers were changing shifts, resulting in higher casualties. ‘The scene is a mess, it’s unrecognisable,’ a witness at the scene wrote on Sina Weibo, a Chinese equivalent of Twitter. Police sealed off the area around the factory, part of a development zone in northeast Kunshan, about 75 kilometres (46 miles) west of China’s commercial hub Shanghai. A large police presence, including officers with riot shields, was stationed outside Kunshan Number One People’s Hospital, where staff said some of the injured were taken. Medical staff has been sent from Shanghai to treat burn victims, the People’s Daily added in an online post. Kunshan mayor Lu Jun announced the latest death toll at a press conference where city officials stood and bowed their heads in front of reporters. More than 260 workers were in the factory at the time, he added. The firm identified by CCTV, Taiwanese-invested Kunshan Zhongrong Metal Products Ltd. says on its website it employs 450 workers.Two senior executives at the firm were detained by police, according to Xinhua. Taiwan’s Central News Agency quoted the company’s general manager as saying two of its staff were ‘under the care of police assisting the investigation’. He added that the factory ‘would be closed for some time’.Forty people were killed at the scene, while more than 20 others died in hospital, CCTV added, showing footage of a huge plume of black smoke. The windows of the factory were blown out in the explosion. Neither the company nor a spokeswoman for General Motors in China was immediately available for comment. Industrial accidents occur with some regularity in China, where safety standards are often lax. A fire at a poultry plant in the northeast of the country killed 119 people last year.Reports at the time said that managers had locked doors inside the factory to prevent workers from going to the toilet, leading to the high death toll. Many local and foreign companies have facilities in Jiangsu province producing goods for export. Kunshan is a centre for Taiwanese investment, with factories supplying China’s vast automotive manufacturing industry. The blast comes two days after at least 26 people were killed in the southern Taiwanese city of Kaohsiung in a suspected gas pipeline explosion. A pipeline explosion in the Chinese coastal city of Qingdao last year killed 62 people and injured 136.