People walk past debris after a fire broke out at a temple in Kollam in the southern state of Kerala, India, April 10, 2016. [Photo/Agencies]

"It was a spark from the crackers being burst that fell into the stack of crackers kept on ground, leading to the fire," another official said.

Local TV channels showed footage of white smoke billowing from the temple and also reported that successive explosions from stack of crackers caused some parts of the temple roof to cave in.

Such was the impact of the fire that Indian Prime Minister Narendra Modi tweeted that the inferno was "heart-rending and shocking," and headed to Kerala to meet the injured in a special Indian Air Force flight, along with a team of 15 specialist doctors from the national capital.

"Fire at temple in Kollam is heart-rending and shocking beyond words. My thoughts are with families of the deceased and prayers with the injured," Modi tweeted and announced a compensation of two lakh rupees (4,000 U.S. dollars) for the families of each of the deceased.

State Chief Minister Oommen Chandy has said the temple had defied orders and carried out the "competitive fireworks", which are a tradition during the ongoing seven-day festival ahead of the New Year of native Keralites.

"A case has been registered against the temple authorities and soon they will be arrested. A judicial probe has been ordered into the fire," the police official said.