The officer-in-charge of Pepermetla police station Premchand Bag had suo motu filed the case a day after the incident at Chitrakonda police station, Malkangiri sub-divisional police officer Umashanker Das said.
The case was registered against Maoist leaders Prasad, Anand Rao, Chenti and others under various sections of Indian Penal Code and the Arms Act which included abduction and other activities, the police said.
"The police had registered the case suo motu and necessary steps would be taken in due course," they said.
Collector R Vineet Krishna and JE Pabitra Mohan Majhi were abducted by the Maoists on February 16 from Pepermetla when the senior government official was going to Badapada to hold a jansampark sibir (public awareness camp).
The collector was released by the Maoists after remaining in captivity for nine days on February 24, following hectic parleys between the state government and Maoist-chosen mediators. The engineer was released on February 22.