The collapse of a series of buildings built by local villagers and packed with migrant workers in China has killed at least 17 people, according to the government and reports. The four multi-storey residential buildings caved in during the early hours of yesterday in Wenzhou in the eastern province of Zhejiang, the Lucheng district government said in a social media posting. By the evening, 17 were confirmed dead and six had been rescued, it said.The official Xinhua news agency said rescuers were still verifying the number of people trapped under the debris. But it cited survivor Yan Yongfa, a 57-year-old migrant worker, as saying that each room housed at least two to three people - many of them migrants like himself. Fire department officer Sun Jing told Xinhua: "To protect those who are trapped, we are mainly digging with our bare hands, so work is going slowly." The cause of the collapse is still being investigated.