However, the roots of the Killer Squadron trace back to 1969, when the Indian Navy inducted Osa-class missile boats from the Soviet Union.

These vessels were transported to India on heavy lift merchant ships and were commissioned in early 1971 at Kolkata (then Calcutta).

On the night of December 4–5, 1971, the squadron launched a surprise offensive, codenamed Operation Trident, against the Pakistan Navy.

This operation dealt a significant blow to the Pakistan Navy, with no casualties sustained by the Indian forces.

These vessels were outfitted with advanced weaponry, including 16 SS-N-25 'Switchblade' (URAN E) missiles, an OTO Melara 76 mm naval gun, and the MR 352 Positiv-E (NATO: Cross Dome) radar system.