Authorities are racing to find a canister of potentially deadly radioactive material stolen from a northern China construction site and are urging those who took the material not to risk radiation poisoning by opening it, officials said Wednesday. The football-sized lead container of cesium-137 was taken from a power plant construction site in Pucheng, a county in northern China’s Shaanxi province, about five days ago, according to a county government official, who refused to give his name. He would not provide further details. A report in the state-run newspaper China Daily said police believe the canister was mistaken for scrap metal — a material often stolen for sale to salvage companies. Full Story