The ultras slit the throat of Subhra Huika (30), with a sharp edged weapon at Odia Pentha village in Narayanpatna area, about 85 km from here late last night, Koraput Superintendent of Police Awinash Kumar said.
A letter bearing the name of Koraput-Srikakulam Division of Maoists was recovered from the spot which warned that anybody passing on information to the police would meet the same fate, police said.
Huika was eliminated as he was acting as an informer of the police, they said.
A massive combing operation has been launched and patrolling intensified in the area after the incident.
The killing came four days after Maoists killed a 50-year-old man in a remote village under Bandhugaon police station area of the district on June 8 night.
The victim was identified as Meleka Taudu of Manasdapadar village.