An explosion and fire at a pharmaceutical factory in Telangana, southern India on Monday killed at least 12 people and injured many others, officials said.

The incident took place at a unit of Sigachi Industries in the state’s Sangareddy district. Firefighters were called to respond to the blaze.

The fire caused part of the building to collapse, trapping workers under the debris.

Damodara Raja Narasimha, a state minister, confirmed the death toll and said a total of 34 people were under treatment.

Chief Minister Revanth Reddy inquired about the accident, and issued orders to intensify relief measures, his office said. He directed that all necessary actions be taken to rescue the workers trapped and provide emergency medical assistance to the injured.

Prime Minister Narendra Modi said he was “anguished” by the loss of lives. “Condolences to those who have lost their loved ones. May the injured recover soon,” he wrote on X, announcing compensation for the kin of the deceased and also to those injured.

G. Vivek Venkataswamy, the state’s labor minister, met the victims undergoing treatment and assured their families of full support from the government.

Meanwhile, an investigation was launched to determine the exact cause of the incident.