Acting on a tip-off, a team led by Superintendent of Police Nitul Gogoi, launched an operation in Bogolamari area of Dudhnoi police station last night to rescue Meghalaya Sericulture Officer Dilip Dutta Medhi.
The militants ambushed the police team and an encounter followed in which four militants were killed and two managed to escape while the kidnapped official was rescued, police said.
Combing operations were continuing in the area and the rescued official was brought to Dudhnoi for medical treatment, they said.