HEFEI, June 30 (Xinhua) -- An explosion at a chemical factory in Bengbu, east China's Anhui Province, during the rescue of a worker trapped in a storage tank, has killed two person and injured nine others, the local emergency response authority said Sunday.

The accident occurred at around 6:00 p.m. Friday in Anhui Maiqi Chemical Co., Ltd, officials said.

A worker of the company was trapped when cleaning the storage tank under construction. In the process of rescue operation, the storage tank exploded, killing the worker and one firefighter on the spot, and injuring nine other first responders.

All injured have been hospitalized.

An investigation is ongoing.