The tragedy occurred in the city of Calcutta (Kolkata) during the Durga Puja festival, which is held at the end of October.
West Bengal state leader Suvendu Adhikari said a 7-year-old girl was among the dead. Late Saturday, he said only six bodies had been identified.
A police officer at the scene said the crowd had "started moving" when the downpour occurred. Many people outside the festival's main building were trying to get away, and the tragedy occurred when people fell and were trampled to death in the rush.