Eight people have died, with hundreds of others taken ill, after a gas leak in south India.
The leak, in the city of Visakhapatnam in Andhra Pradesh state, has been traced to a polymer factory.
Doctors told BBC Telugu that “hundreds” of people have been taken to hospital – many complaining of a burning sensation in the eyes and difficulties breathing.
The incident took place at around 03:00 local time (21:30 GMT) at the LG Polymers plant.
Rajendra Reddy, a senior official in the Andhra Pradesh Pollution Control Board, told BBC Telugu’s Satish Balla that the leaked gas was styrene, which is usually refrigerated.
The incident took place when the plant was being re-opened for the first time since 24 March when India went into lockdown to curb the spread of coronavirus.
Officials told the BBC that they still don’t know what caused the incident and that they are investigating.
As the gas spread, residents ran out of their homes in panic.
It is feared that the fumes have spread over a radius of about 3km (2 miles) and officials have been evacuating people from surrounding areas.
A senior district official told the BBC that initial attempts to control the gas leak were unsuccessful – and that it could take a few hours to bring the situation under control.
In the meantime, officials have asked people to protect themselves by covering their faces with a wet cloth.
India has a sad history of gas leak tragedies.
In 1984, a chemical leak in a plant in the central city of Bhopal killed thousands of people, in what is acknowledged to be the world’s worst industrial disaster.
More than 35 years later, victims say children are still being born with disabilities because of the effects of the spill.