The body of the slain District Intelligence Bureau officer Sadhu Chatterjee was fished out from the Haldi riverbed on Saturday four days after he was lynched by a mob.
The body, which had multiple injuries, was identified and sent for post mortem.
There were severe head injuries with the stomach ruptured, the police said.
The District Intelligence Bureau sub-inspector was attacked and killed on February 7 at Ishwardehajalpai in East Midnapore district when he accompanied police to an area where roads were being dug up by people to prevent forces from entering their villages.
Divers had been searching the Haldi river for the body.
Meanwhile, the Bhumi Uchhed Pratirodh Committee claimed that the men in villages had fled their homes in fear of the Communist Party of India (Marxist) and police.
With PTI Inputs
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