BEIJING, Mar 3 (AP) -- At least 20 grade school students were killed when a cache of explosives stored at the nearby home of a coal mine manager blew up in a town in northern China, news reports said Thursday.

The explosion occurred Wednesday in Kecheng, a town in Shanxi province, one of China's biggest coal-mining regions, newspapers reported.

"Grade school students who were in class were buried," the Shanxi Commercial News said.