By Subir Bhaumik BBC News, Calcutta

The specialist counter-insurgency force courted controversy in July when soldiers of the force were accused of raping and killing a 32 year old.

That incident in the state of Manipur provoked fierce street protests.

The soldier was arrested and charged in Assam's Diphu town in Karbi Anglong district, where he was posted.

Police said two local women alleged to have helped the soldier in the crime were also arrested.

Karbi Anglong police superintendent Pankaj Sarmah told the BBC a medical test on the girl proved she was raped.

Doctors in Diphu say the girl was allegedly lured with food that was laced with sedatives.

Mr Sarmah said the incident took place last week.

The Karbi Tribal Students Association has started agitating against the incident.

Police say that both the soldier and the two women are now in custody now after a remand from a local court.

Analysts say the incident strengthens the demand by human rights activists in North-east India to scrap the federal anti-terror law, the Armed Forces Special Powers Act.

The law gives sweeping powers to troops involved in counter-insurgency operations.