Inspector General of Police Sanjeev Marik said that Maoists opened fired on them when about 30 policemen had gone to raid a rebel camp in a forested area near Parlakhemundi town.
A gunfight between the Special Operation Group (SOG) and the Maoist ensued for almost 3 hours which left 4 policemen seriously injured and 10 others with less-serious injuries.
"We lost two Special Operation Group (SOG) personnel and a local policeman," he said.
The dead were identified as Sanjeet K Tirkey, Balram Pradhan and Deepak Sonbhoy.
Four jawans were shifted to Vishakhapatnam as their condition was stated to be critical.
Police officials said that it is not yet ascertained that there was any casualty from the