Three people were injured in a chemical plant blast in east China's Fujian Province at around 6:56 pm Monday, provincial authorities said.

All the three people are being treated at a hospital, the provincial bureau of workplace safety said, without specifying the extent of their injuries.

Some 430 firefighters are battling the fire in Zhangzhou city.

This is the second accident in 20 months at the same facility that produces paraxylene (PX), an industrial chemical used for making fiber and plastics.

Windows were broken at a gas station one km away from the blast site. No one at the gas station was injured or dead, authorities said, adding that all have been evacuated.

Pictures posted by netizens on the Chinese equivalent of Twitter show flames and fumes rising from a plant, with witnesses reporting strong tremor felt as far as 50 km away from the blast.

PX plants are highly controversial projects in China. All the proposed plants have met strong public opposition in recent years.

China's environmental minister urged during the country's annual parliamentary session in March that construction of PX projects be scientifically decided and must pass environmental impact assessment.