Fearing social stigma, a 25-year-old unwed mother sold her newborn girl for Rs 600 in Bhawanipatna village in Kalahandi, Orissa, and disappeared after the incident.

Kusum Majhi handed over her 20-day-old baby to Dhanu Nayak, a rickshaw-puller, on Thursday and disappeared after the incident came to light, sources said.

Majhi had approached Nayak to adopt the baby on "compassionate grounds". Nayak, who has an eight-year-old son, consulted his family members before agreeing to keep the baby, the district administration said in a statement.

But at the time of accepting the baby, Nayak obtained a written statement from Majhi stating that she had sold the baby to him to "obviate any future legal complication", it said.

"Dhanu has, of course, paid some money to her admittedly not for purchasing the baby but for helping the woman and her mother to go back to their village," the statement said.

"In all probability, it seems the fear of social stigma prompted Kusum to get rid of the newborn baby," it said, adding, "their whereabouts are not known either to their relatives or neighbours."