Hurling stones and setting government vehicles and public property on fire, the agitators went on the rampage in the town, about 600 kilometres from Tamil Nadu's capital Chennai. Tamil Nadu Chief Minister EK Paliniswami expressed grief over the deaths but justified the police action, stating that they had to open fire under "unavoidable circumstance".
The government committed a "Himalayan blunder" by handling the protest with "guns and teargas shells", he said, adding at least a minister accompanied by the district collector should have spoken to the agitators. Kumarattiyapuram residents claim that discharge from the copper plant had polluted the water in the area.
Police said section 144 of CrPc has been invoked in and around the Sterlite unit to provide security to it as per the orders of the Madras High Court.
Social activists have also joined the protests against the company. Heavy police deployment could be seen in Thoothukudi and surrounding areas of the coastal city.
"Since protesters indulged in violence, the police had to resort to firing to bring the situation under control", the government statement said. Other political leaders have also slammed police and the state government.
Chief Minister E Palaniswami, confirming the nine deaths, announced a judicial inquiry into the violence.
Sterlite Copper, the company at the centre of the controversy, now operates a 400,000-tonne per annum unit in the city. "If possible, it will be good to close down the (existing) unit", Makkal Neethi Mayyam chief Kamal Haasan said. They claim that copper plant contaminated the groundwater and caused respiratory problems.
To mark the 100th day of the protests, a march towards the district collector's office was organized to demand the shutdown of Sterlite Industries Ltd's plant.
Palanisamy, however, announced a compensation of Rs 10 lakh each for those killed during protest and Rs 3 lakh each for the injured, besides offering government jobs for the family members of the deceased.
It said in March this year, the company had applied for removal of consent to operate (CTO) for its existing smelter plant. He said the government had expressed strong concerns against the plant's expansion in an ongoing litigation at the Tamil Nadu Pollution Control Board Appellate Authority, which had adjourned the case to June 6.