However, most of them have been discharged after treatment while 10 to 12 workers, who have been admitted to a private hospital, are stated to be out of danger and being kept under observation, Deputy Commissioner of Police (southeast division) B N S Reddy said.
"Though we suspect the gas to be chlorine, we are still ascertaining it," he said.
A case has been registered against the owner of the factories that used to bleach waste garment bits and make them usable, Reddy said.
The cylinder in all probability was dumped by the owner, he said.
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