Bhagat applied himself to his studies in his final year and was commissioned in the British Indian Army on 15 July 1939 as a Second lieutenant (2Lt.)
On 6 November, Slim launched an attack on the fort of Gallabat, with the assault spearheaded by the 3rd Royal Garhwal Rifles, under Lieutenant-Colonel S.E.
With the enemy closing in, Bhagat dashed out from under cover and, with bullets flying all around him, detonated the remaining explosives and collapsed the culvert.
On 31 January 1941, a mobile column of 3/12 Royal Frontier Force Rifles, including a detachment of 21 Field Company under Second Lieutenant Bhagat, was sent on a reconnaissance mission towards Metemma.
Under close enemy fire and without food or rest, he worked for four days, clearing a total of 15 minefields over a distance of 55 miles.
[2]: 286 After having another Bren carrier blown up under him on 2 February, which resulted in punctured eardrums, he was relieved of further duties and evacuated to Khartoum for treatment.
He was decorated with the Victoria Cross later that month and presented with the ribbon by General Wavell (later Field Marshal the Earl Wavell), the Commander-in-Chief, India in June at Asmara and formally invested with the decoration by the Governor-General of India, Lord Linlithgow, at Viceroy's House in Delhi on 10 November.
Royal Bombay Sappers and Miners during the Second World War when the following deed took place for which he was awarded the Victoria Cross: His Majesty The KING has been graciously pleased to approve of the award of the Victoria Cross to the undermentioned officer: — Second-Lieutenant Premindra Singh Bhagat, Corps of Indian Engineers (serving with Royal Bombay Sappers and Miners).
During the pursuit of the enemy following the capture of Metemma on the night 31 – 1 January February 1941, Second-Lieutenant Bhagat was in command of a section of a Field Company, Sappers and Miners, detailed to accompany the leading mobile troops (Bren Carriers) to clear the road and adjacent areas of mines.
He refused relief when worn out with strain and fatigue and with one eardrum punctured by an explosion, on the grounds that he was now better qualified to continue his task to the end.
On 1 September, after the dissolution of the Punjab Boundary Force, Bhagat was promoted to acting lieutenant-colonel and appointed CO of the Royal Engineers, 4th Infantry Division.
[9] In 1954, he was promoted to lieutenant-colonel and assigned as the Chief Instructor (Army Wing) at the Defence Services Staff College at Wellington.
[11] During his tenure, Bhagat completed a thorough assessment of the Chinese Army's threat to India, but his report was not heeded before the 1962 Sino-Indian War.
[20][21] However, after only ten months at DVC, Bhagat died on 23 May 1975 of anaphylactic shock after an injection of penicillin, to which he was allergic, by a careless military doctor.
[22] The Indian Army has dedicated a Chair of Excellence in his memory at the United Service Institution of India (USI).
USI and the Bombay Sappers also organise the annual Lieutenant General PS Bhagat Memorial Lecture.