The Tamil Nadu Pollution Control Board cut power supply to Sterlite Copper’s Thoothukudi smelter on Thursday morning, News18 reported. In an order on Wednesday, the board said it had found the unit was “carrying out activities to resume production” despite being told not to do so until its licence to operate is renewed.

Earlier on Wednesday, the Madurai bench of the Madras High Court had issued an interim stay on the expansion of the plant. In April, the pollution control board had rejected the Vedanta-owned smelter’s application to renew its licence to operate beyond March 31.

The number of protestors who died in police firing during an agitation against the smelter in Thoothukudi rose to 13, while 70 injured people are undergoing treatment, ANI reported on Thursday. Eleven protestors were killed on Tuesday and two on Wednesday. The police have arrested 67 people for indulging in violence.

The Tamil Nadu government on Wednesday suspended internet services in Thoothukudi, Kanyakumari and Tirunelveli districts for five days. Security forces have been deployed in large numbers in the sensitive areas.

Opposition parties in the state, including the Dravida Munnetra Kazhagam, the Congress and Left parties, have called for a dawn-to-dusk shutdown on Friday to condemn the police action against protestors, PTI reported. The DMK said it would also demand the closure of the copper smelting plant.

Congress leader Ghulam Nabi Azad likened the incident to the Jallianwala Bagh massacre in Amritsar in 1919. “The state government knew that this [Tuesday] being the 100th day of agitation, was going to be bigger,” Azad told ANI. “They should have made better arrangements to maintain law and order but nothing was done. They simply resorted to firing.”

The state government had on Wednesday transferred Superintendent of Police (Thoothukudi) P Mahendran and Thoothukudi District Collector N Venkatesh.

For more than two decades, activists in Thoothukudi have accused Sterlite of contaminating the region’s air and water resources, causing breathing disorders, skin diseases, heart conditions and cancer. Since February, there have been protests in Thoothukudi where Sterlite runs the copper smelter with the capacity to produce 4.38 lakh tonnes of copper anodes per annum, or 1,200 tonnes per day.