A blast at an explosives plant in eastern China killed at least 20 workers and injured two, the government said Sunday. The blast occurred Saturday at an explosives packing workshop owned by 761 Explosive Co. Ltd. in Zhaoyuan city, in the coastal province of Shandong, the official Xinhua News Agency said, citing a local official. The report said 31 people were in the workshop when the blast occurred. Rescuers were searching Sunday for nine workers still missing, it said. The two injured were hospitalized in stable condition, it said. An investigation into the cause of the explosion was underway, it said.