Thrissur City Police Commissioner Nakul Rajendra Deshmukh on Tuesday said the cause of the blast at the fireworks storage facility in Mundathikkodu would be known only after a preliminary investigation. At least 13 people were killed and more than 40 injured in the incident.

Addressing the media at the site, Deshmukh said a detailed inquiry, including a fire audit and witness statements, was required to establish the reason behind the explosion. “Those admitted to hospital are not in a position to speak now; once they are able to, we will have more clarity”, he said.

The blast occurred on Tuesday afternoon at a unit storing firecrackers for the annual Thrissur Pooram festival, which began on Monday.

District Collector Shikha Surendran visited the site and said expert medical care was being provided to the injured. Additional medical teams from Palakkad have been deployed. “We have divided the affected into zones and are providing treatment accordingly. Extra water tanks have been arranged for the fire force, and other hospitals have been alerted. At present, the patient load is manageable at the medical college”, she said.

Thrissur Municipal Corporation Mayor Niji Justin said the fire had largely been brought under control and no further explosions had been reported for over an hour, though several of the injured remain in critical condition.

CPI leader V S Sunilkumar described the incident as “heartbreaking” and called for an expert investigation, noting that the blast occurred despite safety measures being in place.

The Thrissur Pooram festivities had commenced with flag-hoisting ceremonies at the Thiruvambady Temple and Paramekkavu Temple, along with eight other participating temples.