Also in 1921 IMRO created as a satellite organisation the Internal Western Outland Revolutionary Organisation, which operated in the areas of Tsaribrod and Bosilegrad, ceded to Yugoslavia.
In the conflict, a Bulgarian victory that defended the revolution, Mutkurov headed the troops fighting at Tsaribrod on 13 November and was also in charge of the central and right wing forces during the Pirot Offensive on 14 and 15 November.
They also cross the border to include the dialects or subdialects of the Bulgarian minority in the Western Outlands (the regions of Tsaribrod and Bosilegrad), Bulgarian territories transferred to Serbia by the Treaty of Neuilly as punishment for Bulgarian participation in World War I on the side of the Central Powers.