Chinese chemical plants have come under scrutiny again when six people were hospitalised and hundreds of firefighters were deployed to fight a huge fire following an explosion at a plant in Zhangzhou, Fujian province, southern China that produces paraxylene (PX). The official Xinhua news agency said strong tremors were felt up to 50 km away.

The accident happened at the Goure PX plant reportedly operated by Taiwan-based Xianglu Tenglong Group and its subsidiary, Dragon Aromatics (Zhangzhou). This is the second explosion to hit the factory in 20 months, with a less serious blast in July 2013.

Authorities said there were no leaks from the plant's three tanks and no signs of contamination of the environment. Concerns over the safety of plants that make PX, a chemical used for producing fibres and plastics, have prompted several protests in China in recent years. Exposure to the chemical can cause eye, nose and throat irritation.

The plant was slated to be built in the densely populated city of Xiamen in Fujian, but protests in 2007 by residents concerned about potential health hazards succeeded in getting it moved to a less populated area in Zhangzhou.

Meanwhile, in Inner Mongolia, one person was killed, 100 injured and 50 arrested after 2,000 police broke up anti-pollution protests against chemical plants in the region.

Ethnic Mongols, who make up around 20% of Inner Mongolia’s 24 million population, say the local chemical processing zone had discharged waste directly onto grazing land.

Coal-rich Inner Mongolia is an attraction for chemical plants, but the plants are polluting farmland and grazing land, according to New York-based Southern Mongolian Human Rights Information Centre.

However, in a statement posted on an official microblog, the Chinese government says it will take action against pollution and said that it had ordered the chemical zone to close and shift to another undisclosed location and that it would punish any companies breaking the rule. The statement did not say how many firms would be affected by the order, with only Tongliao Longsheng Chemical stated.

Though the Chinese government has declared war on pollution, vowing to abandon a decades-old growth-at-all-costs economic model that has spoilt much of China’s environment, the orders issued to local governments have not always been enforced.