At least 46 people have drowned, most of them children, while bathing in rivers and ponds swollen by recent floods during the observance of a Hindu religious festival celebrated by millions in north India, authorities said on Thursday.

The dead include 37 children and seven women who drowned on Wednesday in the eastern state of Bihar in scattered incidents across 15 districts, a statement from Bihar’s disaster management department said.

India has seen deadly stampedes during religious events in the past but widespread drowning incidents during festivals are rare.

Local media reported that some of the rivers and ponds in the state had been swollen by floods following heavy rains.

Devotees were celebrating the annual festival of Jivitputrika Vrat, during which women fast for 24 hours and offer prayers for the wellbeing of their children. They also travel to rivers and ponds in their neighbourhood to bathe, sometimes accompanied by their children.

The state government has announced compensation of 400,000 rupees ($4,784) for the families of each of the deceased, the statement said.