Fireworks have become increasingly popular at religious festivals in India, set off by children and adults in streets and in parking lots, as well as on temple grounds. Religious groups and temples, flush with donations, compete to create the loudest, brightest displays. Accidents are common, though the scale of devastation on Sunday was unusual.

Image Officials loaded an injured person into an ambulance after explosions at a temple in the southern Indian state of Kerala on Sunday. Credit... Asianet News, via Associated Press

Hours after the explosions on Sunday, the police in Kerala opened an official criminal investigation of two top temple officials, Mr. Chacko said. The two officials, P. S. Jayalal, the temple president, and J. KrishnanKutty Pillai, the temple secretary, could not be reached immediately for comment.

S. Chandrakumar, a police inspector in the temple town, said the police had begun investigations of 17 people, including the temple leadership, on allegations ranging from culpable homicide to violating the orders of a local authority.

Also on Sunday, the Kerala government ordered a judicial inquiry into the temple deaths, which must be completed within six months.

Mr. Chacko said 106 people had died and 383 others were hospitalized and being treated for burns. The medical officer of Kollam, Dr. C. R. Jaysankar, said many of the deaths occurred when pieces of concrete, knocked loose by the explosions, fell on members of the crowd.

Some of the dead were burned so badly that they were unrecognizable, according to a statement from Thiruvananthapuram Medical College, which received some of the first victims.