MADURAI (Reuters) - An Indian court on Friday said Vedanta cannot reopen its South Indian copper smelter until it hears an case challenging a verdict by the country’s environment court in favor of the conglomerate.

The smelter was ordered shut by Tamil Nadu over alleged pollution that led to violent protests in May, which culminated in police opening fire on demonstrators and killing 13.

The case was filed in the Madras High Court by anti-Vedanta campaigner Fatima Babu, challenging a decision by the national green tribunal which set aside the state government’s order.

In her petition, Fatima accused the court of not giving some of the petitioners a chance to be heard.

Vedanta will appeal to the country’s top court to ask the tribunal’s order to be implemented, the company said in a statement.

The case will be heard on Jan. 21, Fatima said.