Acting on a tip-off, jawans of CRPF, Special Operation Group (SOG) and district voluntary force (DVF) raided the Maoist camp in the forest near Langalkata in K Balang police station area, the police said.
The ultras while retreating into dense forest fired at the securitymen who retaliated, leading to a fierce exchange of fire, Rourkela Superintendent of Police Himanshu Lal said.
Another senior police official said a woman cadre was seen falling to the bullets but her body could not be retrieved as the ultras took it away while fleeing.
The forces found blood mark on the spot and officials who took part in the encounter said they have seen body of a lady being carried away by Maoists.