One man was killed and hundreds of people were sent to hospitals after a huge leak of phosphorus gas from a controversial factory on a tributary of the Yangtze River sent thousands fleeing from their homes. The Xinwen Zhoukan (News Weekly) said the leak occurred early on July 2 in Yanbian, Sichuan province, when a wall collapsed at China's biggest yellow phosphorus producing plant. The leak caused a 30km-long cloud of phosphorus gas to spread over Yanbian, which is only 7km from the plant. Most of the town's 15,000 residents fled in panic to escape the fumes. The town's largest hospital treated 188 patients, of whom 33 were below 14 years of age, and 61 stayed overnight. Five were in critical condition. Another 653 were treated by hospitals in the steel city of Panzhihua, which was also affected by the cloud. Those who fled Yanbian headed south to Panzhihua, on the banks of the Yangtze. Instead of the normal five yuan (HK$4.70) fare, drivers of minibuses charged 30 yuan, while the price of a face mask leapt from one yuan to five yuan. Nearly 700 primary school students in Yanbian had to abandon the annual examination they were to take that day. At the time of the leak, the wind was blowing from the north and carried the cloud south towards Panzhihua, which has a population of 1.1 million. The city's Hygiene Department reported residents inhaled 4.28 times the permitted level of oxidised phosphorus. On the evening of July 2, the city created rain to reduce the impact of the pollution. The dead man was a migrant worker from Yunnan who died fighting a fire that broke out at the plant after the wall collapsed. A Panzhihua government official said the factory had been ordered to shut down until an appointed taskforce had investigated the incident. Yanbian residents have long opposed the plant. They moved to the town, which is just five years old, in 1997 after their former town was submerged under water to build the Ertan dam and power plant. In March 1998, work began on the plant, at a cost of 320 million yuan. The plant produces 60,000 tonnes of yellow phosphorus a year and earned US$22 million (HK$171 million) in exports for Sichuan last year. The phosphorous factory was built at that site because of its close proximity to the Ertan power station, the biggest in China. Because of problems with the national power distribution system, the power station can only sell two-thirds of its capacity. As a result, the phosphorus plant pays only 0.15 yuan per kilowatt hour, the cheapest price in the country. The first major accident occurred in March 2000, when 500 tonnes of fish in rivers close to the plant died suddenly. Yanbian residents blamed this on leaks from the factory. Calling for the plant's closure, residents campaigned the Panzhihua government, their local members of the National People's Congress and the State Council. But the government insisted the plant met health standards and was not a threat to the environment.