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In multiple videos, men, women and children were seen on the streets of Vishakhapatnam, an industrial port city. At least hundred people, many in masks for COVID-19 precaution, were seen lifting the injured and bundling them into waiting ambulances.
Two people were so dizzy that they fell into a well and died. Two more died when their two-wheeler fell into a ditch. One woman fell off the second floor of her building. In one mobile video, a woman standing near a scooter suddenly collapsed on the pavement.
Residents near the plant reported burning eyes and skin and difficulty breathing, officials said. Prolonged exposure to styrene can affect the nerves and even cause kidney damage.
Over 1,000 people have been exposed to the gas, said SN Pradhan, the chief of the National Disaster Response Force. People within a 3 km radius of the chemical plant have been affected.
A failed valve is suspected to have caused the leak. Investigators believe after 40 days of lockdown, gas pressure may have built up. Styrene has to be maintained at less than 20 degrees, but refrigerants may have failed, causing pipes to burst.
Police officer Swaroop Rani in Visakhapatnam was quoted by Agence France-Presse as saying the gas leaked out of two 5,000-tonne tanks that had been unattended due to the lockdown. "It was left there because of the lockdown. It led to a chemical reaction and heat was produced inside the tanks, and the gas leaked because of that," the officer told AFP.
In tweets and announcements, the municipal office warned people in the vicinity of the gas leak and urged everyone to stay indoors. People were also asked to wear wet masks or cover their face with wet cloth.
The plant makes polystyrene, a versatile plastic used in fiberglass, rubber and latex and for making toys and appliances among other things. Set up in 1961 as Hindustan Polymers, the company was taken over by South Korea's LG Chem and renamed LG Polymers India in 1997.
"The gas leak situation is now under control and we are exploring all ways to provide speedy treatment for those who suffer from inhaling the leaked gas," said LG Chem. "We are investigating the extent of damage and exact cause of the leak and deaths," it added in a statement.
The incident has been compared by many to the 1984 Bhopal Gas leak, one of the worst industrial disasters in history when gas leaked from a pesticide plant operated by Union Carbide. Around 3,500 people died. Government statistics say at least one lakh people continue to suffer chronic illnesses.
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