During the 1965 war L.t. Col Raghubir Singh who was commanding the 18 Raj Riffles in Khem Karan Punjab was ordered to occupy the left forward position in the 62 Brigade sector. At Asal Uttar, throughout the night of Sept 7, the battalion assisted engineers by digging and laying minefields. Pakistani troops shelled area and carried out probe missions and finally attacked on Sept 9.

A squadron of Pakistani Patton came up to within 450 meters of the battalion's left flank. The tanks overran the forward company positions. This was accompanied by heavy artillery fire. As communication with the Indian forward position was disrupted, Raghubir Singh anticipating a tank assault, mowed through three enemy tanks as he attempted to reach the forward companies. Unmindful of heavy artillery fire, he successfully re-established communication.

The Indian situation then improved. Inspired by the example , his defiant men destroyed 20 tanks. His courageous feat won him the Mahavir Chakra.

He was posthumously honoured with the MAHAVIR CHAKRA.