More than 2,000 people were arrested Friday in India's remote northeast after a government crackdown on illegal child marriages, police said.
India is home to more than 220 million child brides, according to UN figures, but the number of child weddings has fallen dramatically this century.
The two-week police campaign in Assam state began Friday after chief minister Himanta Biswa Sarma called on public help to abolish the "evil practice".
Sarma said almost one in every eight women in Assam had to bear children before turning 18 which was contributing to high infant and maternal mortality rates in the state.
State police director general GP Singh said 2,044 people were arrested in the first day, including 52 priests and legal authorities who had presided over marriages.
Singh said girls as young as 12 were still being married to men in the state and police had come up with a total of 4,074 cases to investigate.
The legal marriage age in India is 18 but millions of children are forced to tie the knot when they are younger, particularly in poorer rural areas.
Many parents marry off their children in the hope of improving their financial security.
The results can be devastating, with girls dropping out of school to cook and clean for their husbands and suffering health problems from giving birth at a young age.
In a landmark 2017 judgment, India's top court said that sex with an underage wife constituted rape, in a ruling cheered by activists.