CHANGSHA - Police in central Hunan province are hunting for a man who they say used a homemade explosive to blow up a shop in downtown Changsha, the provincial capital, on Wednesday morning.

The man threw the explosive - which appeared to be a homemade firecracker - into a store that sold communication equipment on Santai Street in southern Changsha at 9:30 am, police said.

The blast destroyed glass counters and the shop's ceiling but no one was injured, police said.

Police said the man's extreme behavior resulted from disputes with the store.