At least 27 mortar shells of the 1971 Indo-Pak war period were found in West Tripura district on Thursday, police said.
The shells were discovered when labourers were digging a pond at one Dulal Nama's house.
Initially, 12 mortar shells were found and upon further excavation, another 15 were recovered, police said.
"The mortar shells, estimated to be around 50 years old, were severely damaged," officer-in-charge of Bamutia outpost said.
Villagers suggested the shells might have been buried by members of the Mukti Bahini (Bangladesh freedom fighters) and inadvertently left behind.
Assistant Inspector General Ananta Das confirmed the recovery, noting, "The shells appear severely damaged, making it difficult to determine their exact origins or manufacturing details due to label destruction."
Das suggested that only arms experts could conclusively identify their history.
Mukti Bahini, instrumental in Bangladesh's liberation during the 1971 war, utilised Tripura's border as a strategic base against the Pakistani army.
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