Authorities in southern China have formally arrested 11 people for their role in a landslide unleashed at construction waste dump last month that killed 12 people and left 62 others missing and presumed dead. Prosecutors in the southern city of Shenzhen said in a statement late Thursday that a dispatcher and supervisor of the landfill, the chief and deputy manager of a company in charge of the landfill, and seven other people were arrested. In the Dec. 20 disaster, a mountain of construction waste that had been piled up against a hill collapsed during heavy rains onto an industrial park in Shenzhen. The city near Hong Kong makes products ranging from cellphones to cars, and attracts workers from all parts of China. Prosecutors said the 11 people have been charged with negligently causing a serious accident. They said they have urged police to track down additional suspects. An official in the district where the landfill was located jumped to his death from a building about a week after the disaster. It was not clear if the man, identified only by his surname, Xu, was under investigation over the landslide, but as head of the district Urban Management Bureau, his responsibilities typically would include regulating businesses and construction sites. Officials have labeled the landslide a man-made disaster, raising the possibility of harsh penalties for those held responsible. Despite the threat of prison time over major industrial accidents, a lack of regulatory oversight and cost-cutting by management often lead to deadly disasters in China.