BEIJING, Feb. 11 (UPI) -- More than 200 people were searching in China Wednesday for a football-size lump of explosive and radioactive material known as cesium-137.
The China Daily said the cesium was stolen from a construction site in central Shaanxi province, likely mistaken for scrap metal.
The material explodes when brought into contact with water and can cause blood diseases, tumors and birth defects, officials warned.
At least 120 police officers and 100 local officials began a grid search of two square miles around the site, and a public appeal was issued asking anyone who finds it put it in a safe place.
A reward of $600 was offered Wednesday for its return.
Cesium-137 has a wide variety of uses, from food and medical sterilization to survey gauges and batteries.
It is not clear what it was doing on the construction site, the BBC reported.
