CRPF DIG Umesh Kumar told PTI that paramilitary jawan Sachindra Sharma was killed and 10 other security personnel, including eight jawans of the force and two policemen, got injured in the gun-battle.
Six injured CRPF jawans were undergoing treatment at a primary health centre at Imamganj, while another CRPF jawan Raju Toppo was air-lifted from Gaya to Patna for treatment at the Patna Medical College and Hospital (PMCH).
Another unidentified jawan has been admitted to a hospital at Gaya, he said.
Additional Superintendent of Police Shambhu Prasad and an unidentified Special Task Force (STF) constable were injured in the encounter, Kumar said, adding that the gun-battle was on till late afternoon.
The encounter took place between the security men and the Maoists after the CRPF's CoBRA battalion, STF and Gaya police launched a joint combing operation in the forests after being tipped off about the assembling of a large number of ultras, he said.
The Maoists opened fire and triggered several land mine blasts to deter the advancing security forces who retaliated by firing on the ultras and the encounter ensued since 6 AM.
Superintendent of Police (SSP), Gaya, rushed to the spot with reinforcements to assist the forces as the Inspector General of Police (IG), Operation, Amit Kumar too went there from Patna to monitor the situation, Kumar said.