Operation "Python" was the second and catalytic blow of the Indian navy against the Pakistani counterpart during the Second Indo-Pakistani War in 1971. It was the final blow both materially and especially morally against the Pakistanis who they did not dare to go out to sea again...
On December 4, 1971, the Indian Navy launched Operation Triaina, hitting the port of Karachi, the fuel tanks there and sinking or turning into useless scrap four enemy ships.
However the destruction of the fuel tanks was not total.
Thus it was decided to carry out a new operation ("Python"). The operation would be carried out on the night of December 8-9. The rocket ship INS Vinash would participate in it (Soviet-built Osa class) and the frigates INS Talwar and INS Trishul (British-built Type 12).
Overwhelming attack
On the evening of 8 December 1971 the Indian squadron set sail in very bad weather. Its target was the port of Karachi. The Indian missile launcher carried four Styx surface-to-surface guided missiles. The two frigates carried two 4.5in guns. 40mm Bofors anti-aircraft guns and anti-submarine mortars.
Indian ships sailed unnoticed due to bad weather and approached the Manora Peninsula south of Karachi. A Pakistani patrol boat spotted the Indian boats but before it could report their presence it immediately sank as its ammunition was blown up by Indian fire . But the Pakistani radars detected the Indian ships, as reported by the Indian vice-admiral, Hiranandani.
However, there was no reaction. Thus the Indian ships approached the port at a distance of 14 nautical miles (n.m.). Immediately the Indian missile boat launched its missiles. The first missile hit the fuel tanks causing a terrifying explosion. The second struck the panaima tanker Gulf Star, sinking it.
The other two missiles hit the Pakistani fleet oil tanker PNS Dacca and the British tanker Harmattan, respectively. The first was heavily damaged and rendered useless, while the second sank. After the blow the Indian boats left unmolested.
The result was disastrous for Pakistan. The value of the fuel lost alone was over $3 billion in contemporary prices. As a result, Pakistan faced a fuel shortage that even affected its air force.
But the blow was even stronger to the morale of the Pakistanis. Their navy took emergency measures. Pakistani ships would now carry minimal ammunition to prevent the risk of explosion. It was also forbidden to set sail without a special order, especially at night. Also foreign vessels serving Pakistan's transport stopped sailing to Karachi. Essentially the Indian success resulted in the imposition of an informal naval blockade on Pakistan.