In the western theatre of the war, the Indian Navy successfully attacked Karachi's port in Operation Trident on the night of 4–5 December, using missile boats, sinking Pakistani destroyer and minesweeper ; PNS Shah Jahan was also badly damaged. In response, Pakistani submarines sought out major Indian warships. 720 Pakistani sailors were killed or wounded, and Pakistan lost reserve fuel and many commercial ships, thus crippling the Pakistan Navy's further involvement in the conflict. Operation Trident was followed by Operation Python on the night of 8–9 December, in which Indian missile boats attacked the Karachi port, resulting in further destruction of reserve fuel tanks and the sinking of three Pakistani merchant ships. Since Pakistan's naval headquarters and almost its entire fleet operated from the port city of Karachi, this was a major strategic victory that enabled the Indian navy to attain complete naval superiority, and to partially blockade Pakistan.