A mass grave, containing four bodies of victims suspected to have been killed for their alleged role as informers against extremists group United Liberation Front of Assam, has been unearthed in Assam's Tinsukia district triggering tension in the area.

The bodies were dug out from the grave at Haskati Kung Seng village under Kakopathar police station on Tuesday after the villagers reported presence of human body parts, police said.

The four bodies, which were identified from clothes, were of Mridul Bopatro Gohain, Birbal Lahotia, Suraj Moran and Anil Gohain.

Police said that the outfit's A company, which is now under ceasefire, was responsible for the killing after suspecting them to be police informers.

The area has been cordoned off as police suspected more bodies could be lying in the area.

Meanwhile, Jiten Dutta, former self-styled A company commander of the outfit, has claimed his responsibility behind the attack. It was one of the reasons why he came out, Dutta said.

Similar mass graves were found inside Lakipathar reserve forest by the army during operations in 1991.