Blackburn and fifty men of D Company were detailed to move on the trench where, several hours earlier, John Leak had won the Victoria Cross. D Company were to drive the enemy out. This they did after Blackburn personally led four successive bombing parties, many members of which were killed; the enemy strong point was destroyed and nearly 350 metres of trench were captured. Blackburn was supported by his platoon sergeant, R.M. Inwood (whose brother Corporal Reg Inwood would win the Victoria Cross in 1917), until Inwood was killed.

During World War 2, Blackburn was taken prisoner by the Japanese in Java in 1942, and held until 1945.