At the Battle of Sardarabad in 1918, the 5th Regiment was a reserve guerrilla unit and a special cavalry regiment. His cousin, Daniel Bek-Pirumyan, also participated in the battle as a commander-in-chief. Armenian general Movses Silikyan ordered elements of the 5th Armenian Regiment under Bek-Pirumyan to check the advance of the Ottoman army. An offensive was launched on May 22 and the Armenian forces were successful in halting the Ottomans in their tracks and forcing Yakub Shevki Pasha's forces into a general rout, retreating nearly 15-20 kilometers in a westerly direction. The Ottoman command, however, was able to recuperate from its losses and reorganized its forces near the mountain heights on the north-west bank of the Araks river. Repeated attempts to cross the river were met with fierce resistance by the 5th Armenian Regiment. On May 24, several more skirmishes took place between the Armenian and Ottoman forces. The battle came to end on May 29, with a decisive Armenian victory