At least five people got killed Friday by blasts in the wake of a chlorine gas leak in Jiangbei district of southwestern Chongqing Municipality, firefighters said.

Xinhua reporters at the scene hear loud explosions at about 5:57 p.m. from the Tianyuan Chemical Industry Plant, where the chlorine gas first started leaking around 7 p.m. Thursday.

The highly irritating, greenish-yellow fumes can be smelt near the areas about 300 meters from the plant. Inhalation of 2.5 milligrams of chlorine gas is enough to cause death and symptoms of inhalation include bronchial spasm, dropsy and respiratory difficulty.

Firefighters estimated that at least seven liquefied chlorine gas furnaces, with a load of six tons of liquefied chlorine gas each, are letting off toxic fumes.

Residents living near the scene have to be evacuated again after they were temporarily allowed to return home, said Vice Mayor Zhou Mubing, who is directing rescue work at the scene.

Tens of thousands of people were evacuated Friday as toxic fumes following a chlorine leak filled the air, officials and eyewitness said.

A large amount of chlorine gas was released into the air as from late Thursday evening when a leakage accident occurred at thecity's Tianyuan Chemical Industry Plant. Several blasts were also heard later.

All residents living within a radius of one kilometer of the spot and some residents in an urban area facing the plant across Jialing River were evacuated, the vice mayor said.

"At least 4,000 people were compelled to leave," said a driver who helped displace people from nearby areas.

It was the third chlorine gas leak at the plant since last year,said a worker at the plant, who declined to be named. Sources acknowledged that the municipal government planned to move the chemical plant with a force of about 2,000 workers from downtown areas to Wanzhou district, a new city zone located in the Three Gorges Reservoir area.

The pressure inside the chlorine furnace has now been reduced to 0.25 kilograms per square centimeter from 1.5 kilograms per square centimeter after experts discharged half of the liquefied chlorine in three furnaces.

Source: Xinhua