Amaravati: At least 20 workers, majority of them women, fell sick after a leak of ammonium gas late on Thursday night in a dairy belonging to a private agro products firm at Bandapalli village of Chittoor district in Andhra Pradesh.
While three of the victims were shifted to Ruia Hospital in temple town of Tirupati, five were admitted to the CMC hospital in Vellore in neighbouring Tamil Nadu.
The others were undergoing treatment in the government hospital in Chittoor, police said.
Chittoor district Collector Narayana Bharat Gupta and Superintendent of Police Senthil Kumar visited the dairy unit and supervised the rescue operation.
According to the Collector, the gas leak occurred while some welding work was being carried out in the unit.
"We have ordered an inquiry and the exact cause of the mishap will be revealed only later. The possible human negligence angle will also be probed," Gupta said.
He said the condition of the workers undergoing treatment was stable.