Patna: Police on Saturday evening arrested a man they called a "psycho serial rapist" from a village under the jurisdiction of Kasba police station in Purnea district, around 300km east of Patna.

A police team raided Sabdalpur village in Purnea district and took Kailash Chauhan into custody for the rape of a differently-able girl on the night of August 21 this year.

The girl was found unconscious in a paddy field on August 22, a day after she was kidnapped from her house while she was sleeping. She was rushed to a Bhagalpur hospital where the doctors discovered that she was raped and her private parts were damaged. She is still undergoing treatment at the hospital.

A police complaint was lodged with the women's police station on the statement of the girl's mother.

Purnea superintendent of police (SP) Vishal Sharma said on Sunday that Chauhan, a member of the legal body of the local panchayat, had confessed to the crime.

Sharma said Chauhan's name had figured in earlier rape cases. He was arrested in one case but released on bail.

"The clothes of the (August 21) victim and blood samples of the accused are being sent to the state forensic science laboratory for examination," the SP added.

He said that the case would be put on speedy trial. "Instruction has been issued to the investigating officer to file the chargesheet against the accused at the earliest," he said, adding that Chauhan was arrested on the basis of scientific evidences.

A police officer said under cover of anonymity that several women had earlier written to the SP against Chauhan, who looked after legal affairs at the panchayat. Chauhan, the source said, was earlier also accused of unnatural sex with an animal.

"He seems to be a psychopath rapist," said an investigating officer. On Sunday, Chauhan was remanded to judicial custody for 14 days.