A quantity of a potentially deadly radioactive substance, cesium-137, was stolen from a construction site in Pucheng County, Shaanxi Province, at least five days ago.

Police believe whoever took it may have confused the football-sized lead container used to store the cesium-137 with run-of-the-mill discarded metal scraps.

Cesium-137 is a very active radioactive metal that explodes when brought in contact with water. It is mainly used in photo electronic batteries, vacuum valves and as a test tool in metal surveys.

It can cause blood diseases, sterility and birth defects.

Local officials have asked anyone who finds the football-shaped container not to open it, and to put it in a safe place. Authorities should be notified of the substance immediately.

Police are already actively searching for the stolen material.

As soon as receiving the report about the lost material, some 120 police officers and 80 local officials started searching the more than two- square-kilometers site where the theft occurred.

Local police officers have also been searching in every house in two towns and 14 villages around the construction site. They have also prohibited all salvage stations in Pucheng County from purchasing cesium-137 and asked them to report anyone who may now be trying to sell it.

"As much as 5,000 yuan (US$602) will be given as a reward to any one who provides valuable clues to finding the radioactive matter," local police said.

The theft has attracted attention from the Shaanxi provincial government.

A working group of experts with specialized search equipment was sent to Pucheng, officials said.

So far, they have been working in the area for five days, said Li Zhonghong, group leader, noting the importance of the lost item.

(China Daily February 11, 2004 )