A woman Maoist, carrying a reward of Rs 25 lakh on her head, was killed in an encounter with security personnel in Chhattisgarh's Bastar region on Monday, an official said. The gunfight broke out at around 9 am in a forest along the border of Dantewada and Bijapur districts, located in the region, when a team of security personnel was out on an anti-Naxalite operation, Dantewada Superintendent of Police Gaurav Rai said.