Chennai, Aug 14 (IANS): The Madras High Court on Tuesday ordered a probe by the Central Bureau of Investigation (CBI) into the police firing in Tuticorin in which 13 people were killed on May 22. The victims were taking part in a protest against the Sterlite copper smelter plant.

The court also quashed the charges slapped against six protesters under the National Security Act for their role in the violence.

The copper smelter plant owned by Vedanta Ltd is located in Tuticorin around 650 km from here.

About 60 persons were injured in the police firing.

Earlier Chief Minister K. Palaniswami told the media that people in Tuticorin had been protesting peacefully for long against the company, alleging that it was causing health hazards and depleting the water table, but this time, the opposition and "anti-social elements" had turned the movement violent.

"It is because of this instigation that so many people have died. And we are really saddened by the deaths," he said.

According to an FIR lodged by Tuticorin police, a Deputy Tehsildar has claimed that he had ordered police firing on May 22 against the anti-Sterlite Copper protesters.

The FIR filed by the police on May 22 says that Sekar, Deputy Tehsildar in Tuticorin, admitted that it was he who had ordered the police firing at the protesters after all the other steps to restore law and order failed.

As per the FIR, Sekar said he had at first warned the protesters that force would be used and when this did not work, he ordered a baton charge. When this proved inadequate and the crowd kept surging forward menacingly and attacked the police personnel, he had ordered the firing of tear gas shells after due warning.

The official said when tear gas shells failed to disperse the violent mob, which was destroying public property and attacking the police personnel near the Collectorate, he ordered firing as the last resort. Twelve persons were killed in police firing on May 22 and later one more person died in a fresh firing.