A fire fighter walks at the site where an ammonia gas leak occurred at Chifeng Pharmaceutical Factory in Chifeng City, north China's Inner Mongolia Autonomous Region, on Aug. 5, 2009. A total of 202 people fell ill after the ammonia gas leak here on Wednesday. The leak occurred at 8:40 a.m. when a truck carrying 30 tonnes of liquid ammonia was unloading at the factory of Chifeng Pharmaceutical Group, but was sealed in about 50 minutes, the government said.[Xinhua]