A woman Maoist was killed and three security personnel injured in an exchange of fire between the two sides at Pallur in Koraput district early today.

The exchange of fire took place when jawns of Special Operation Group, the state's elite anti-naxal force, were going on a combing operation in Pallur area under Narayan Patna police station, Y J Rao, SDPO of Narayana Patna, said.