Zambia's Ministry of Mines and Minerals Development has dispatched a team of inspectors to investigate an accident at Chinese-owned Collum Coal Mine which left at least 22 miners injured Sunday, a government official said Tuesday... Collum Coal Mine...officials couldn't be reached for an immediate comment... State news agency Zanis Tuesday quoted an injured miner as saying the accident was caused by an increase in air pressure, after an airbag supplying oxygen to an underground shaft burst.