A woman Maoist of the group, identified as Lalita alias Sunita, was arrested, Bokaro Superintendent of Police Y S Ramesh told reporters here.
The encounter began around 7 PM last night and lasted till around midnight near the village situated in the foothills of Jhumra hills, Ramesh said adding, the Police were trying to establish the identity of the dead extremist.
Two rifles, bullets, blankets and medicines were recovered from the encounter site, he said.