A fire swept through a packed Hindu temple in the southern state of Kerala, India, during a fireworks display early Sunday, killing more than 100 people.

At least 200 other people were injured, NPR's Julie McCarthy reports from New Delhi.

She tells our Newscast unit that, as army and naval personnel mobilize to aid local medical teams, authorities are starting to investigate what caused the explosion at the temple in the town of Paravoor:

"An estimated 10,000 people had crammed into the complex to celebrate the start of the local Hindu New Year. As a late night fireworks display was coming to an end, a deafening explosion erupted. It was powerful enough to flatten one of the buildings in the compound."

Kerala's top elected official, Chief Minister Oommen Chandy, said that "the fire started when a spark from the unauthorized fireworks show ignited a separate batch of fireworks that were being stored at the Puttingal temple complex in Paravoor village," according to The Associated Press.

Revelers were trapped inside the temple complex, and most of the people died after the structure used to store fireworks collapsed, Chandy said.

Kerala is studded with temples that are managed by powerful trusts.

While the investigation is still ongoing, initial reports suggest temple officials may have proceeded with an annual fireworks competition even though they didn't receive permission from authorities, disregarding other safety precautions, as well.

"The local magistrate said permission to hold a fireworks competition had been denied. Despite that, local media say that's exactly what was happening," Julie reported. She adds: "Where were the authorities to enforce their own ruling?"

Police official Loknath Behera tells the AP that temple authorities also ignored a court order mandating that fireworks "must be stored more than 100 meters from temples."

The Press Trust of India reports that a case has been registered "against temple authorities and explosive licensees." They're accused of "attempt to murder" and "attempt to commit culpable homicide."

But authorities may have trouble finding them: According to The Times of India, local police say top temple officials have "gone missing."

Eyewitness Krishna Das describes the first moments after the explosion to the AP: "It was complete chaos. People were screaming in the dark. Ambulance sirens went off, and in the darkness no one knew how to find their way out of the complex."

Later, "charred bodies and human remains were strewn around the temple complex," according to PTI.

Indian Prime Minister Narendra Modi flew to Kerala on Sunday, and video posted by local media outlet ANI showed him surveying the scene of the explosion. He came with teams of doctors to help local authorities cope with the injured patients. In a tweet, he called the temple fire "heart-rending" and "shocking beyond words."

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