At the dawn of 04 December 1971 three Hunters from OCU, Jamnagar attacked the oil storage tanks (Kiamari oil tanks) located at Karachi harbor and set it on fire. The attack was led by Wg Cdr Don Conquest, Commanding Officer of Operational Conversion Unit (OCU). Other members of the formation were Sqn Ldr (later Gp Capt) S.N. Medhekar, Flt Lt. (later AVM) P.K. Mukherjee and Flt Lt. (later Wing Cdr) S.K. Gupta. For Hunters Karachi was at the extreme range from Jamnagar. As such Pakistan probably never thought of attack developing from Indian fighters at low level from the direction of the sea. Defying all odds the leader Don Conquest planned the mission to fly low level over the sea and approach the target from the West and carry out a single pass gun attack and getaway towards East to reach the Indian mainland at the shortest time possible. Complete element of surprise was essential as the PAF had its presence at Masroor airbase that was very close to the target area. As the aircraft pulled up over the target, they made contact with the huge number of oil storage tanks located at the harbour and went into the attack. The 30 mm high explosive rounds fired from the lead Hunters guns impacted storage tanks and huge ball of fire erupted. Number two Hunter then pressed home his attack into another set of tanks. The smoke from the burning tanks was so intense that last aircraft could barely see the ground through the smoke haze. Mission accomplished, the formation once again hugged the deck and headed for home before the defences over the target area could react. The attack by Hunters was followed by Indian Navy on 05 December 1971 and IAF Canberra bombing of the refinery on 08 December 1971. The sustained attacks on Karachi refinery and oil storage facilities were responsible in drying out the fuel supply for Pakistan to sustain the war effort.