Some labourers spotted human limbs protruding from under a polythene sheet.
The police said the victims had been blindfolded with their hands tied behind and shot in the head a week or more ago.
“The bodies bore bullet wounds in the skull. We hope to identify them following an autopsy,” VZ Angami, Dimapur superintendent of police, said.
But his counterpart in Assam’s Karbi Anglong district (bordering Nagaland), Mugdhajyoti Mahanta, said a Karbi man claimed he went to Dimapur and identified one of the bodies as that of his brother.
“The man said his brother sported an unmistakable tattoo and was missing since he went shopping to Dimapur last month,” Mahanta said.
The execution is seen as the fallout of the clashes between Karbi and Naga militant outfits in Karbi Anglong. Nine persons, seven of them Nagas, were killed in those clashes.
Meanwhile, suspected Naga militants on Saturday evening attacked a Karbi village in Assam and killed one person