JAIPUR (AFP) - Indian officials have freed 51 children kept in "pathetic conditions" in the city of Jaipur amid suspicions they were held as part of a human trafficking racket, officials said on Thursday.

The state-funded Rajasthan Commission for Protection of Child Rights said 27 girls aged between seven and 17 years were among the children found on Tuesday in two homes.

Commission chief Deepak Kalra said officials raided the two premises, which claimed they were working as children's homes, following a tip-off from a New Delhi-based activist organisation.

"The children mostly from states in the northeast were brought here on the pretext of providing education by one Jacob John but they were confined to the homes here," the commission chief said.

Jaipur is the capital of Rajasthan state, which is popular among tourists.

"The children were not allowed to go outside, even people living nearby were unaware that such a centre was functional in the area," Ms Kalra said.

State Rajasthan Women and Child Development Minister Bina Kak said a probe was under way.

"They lived in pathetic conditions but whether they were exploited or not is a matter of investigation," Ms Kak said, adding that police had arrested the owner of the two homes.

India's federal detectives said last year that there were 815 gangs comprising of more than 5,000 members involved in the kidnapping of children for prostitution and begging across India.

An estimated 50,000 children go missing every year in India, according to a petition.

"Young women are regularly kidnapped by traffickers and sold into marriages," prominent activist Rishi Kant of the New Delhi-based Shakti Vahini child rescue group told AFP.

A government-appointed panel re-writing India's anti-rape law in January proposed tougher punishments to combat human trafficking.