Dravida Munnetra Kazhagam leader Kanimozhi and other Opposition members in Tamil Nadu were detained in Chennai during a dawn-to-dusk shutdown on Friday to condemn the police firing on anti-Sterlite protestors in Thoothukudi, ANI reported. Security was stepped up across Thoothukudi city, and around 20,000 security personnel were deployed in sensitive areas, The New Indian Express reported.

Viduthalai Chiruthaigal Katchi leader Thirumavalavan was also detained. The Congress and Left parties are backing the strike. The DMK on Thursday said it would demand the closure of the controversial copper smelting plant run by Sterlite Copper.

Meanwhile, internet services were restored in Thirunelveli and Kanyakumari districts after the home department wrote to the district administration and telecom service providers, News18 reported. The authorities on Tuesday had suspended internet services in Thirunelveli, Kanyakumari and Thoothukudi districts.

The Madras High Court on Thursday rejected the Tamil Nadu government’s plea seeking to reconsider a ruling passed on Wednesday to preserve the bodies of the protestors who were killed in the police firing, reported The Times of India. The government argued that storing the bodies would lead to rapid decomposition and that keeping them in the hospital might become a ‘focal point of unnecessary unrest’ in Thoothukudi. A division bench refused to pass an interim order and told officials to preserve the bodies till May 30.

Thirteen protestors were killed in police firing on Tuesday and Wednesday during an agitation against the smelter in Thoothukudi. Chief Minister Edappadi K Palaniswami on Thursday blamed “certain political parties, non-governmental organisations and anti-social elements” for the violence, and said they had taken the protestors down the wrong path.

About 40% of the buses in the state and many auto rickshaws are expected to stay off the roads after various trade unions said they would support the shutdown. All transport workers’ unions and employee unions will participate in the strike and buses will not operate between 6 am and 6 pm, K Natarajan, the treasurer of Labour Progressive Federation, told The New Indian Express. Auto Drivers’ Association General Secretary Shivaji told Firstpost that auto rickshaws will not run on Friday across the state for the 12-hour strike.

On Thursday, DMK Working President MK Stalin and other party leaders staged a protest outside the Tamil Nadu secretariat. Stalin was evicted from Palaniswami’s office and was detained briefly. He has demanded the resignation of Palaniswami and Director General of Police TK Rajendran.

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.

On Thursday, the Tamil Nadu Pollution Control Board cut the power supply to the smelter. 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.