The organization continued to operate as an underground network in the Socialist Republic of Bosnia and Herzegovina and eventually disappeared after its leadership was arrested by the communist Yugoslav authorities in 1949.
In order to avoid being abolished or merged into an Ustaše organization, Young Muslims transformed into the youth branch of El-Hidaje.
On the one hand, within El-Hidaje they organized religious activities, including meetings, congregational prayers, and celebrations of Muhammad's birthday.
On the other hand, they participated in the charitable organization Merhamet (English: "Charity") and took care of Muslim refugees from eastern Bosnia and Herzegovina.
At the same time, Bosnian Muslims were victims of the Chetnik massacres, which were also partly a reaction to the repressive Ustaše policies against ethnic Serbs.
At the end of the war, however, the majority of the division joined the communist Yugoslav Partisans led by Josip Broz Tito.
The communist Yugoslav authorities abolished El-Hidaje altogether, and the Young Muslims afterward became a clandestine and completely autonomous organization.
[3] World War II and the official atheism of the new communist government led to further politicization and radicalization of Young Muslims.
Unlike the group in Mostar, which to some extent managed to spread to the rural population and make preparations for armed struggle, the rest of the Young Muslims were very limited in their activities.
However, with Tito–Stalin split, which was a result of the culmination of a conflict between the political leaderships of Yugoslavia and the Soviet Union, Young Muslims suffered greatly.
Four of them – Hasan Biber, Halid Kajtaz, Omer Stupac, and Nusret Fazlibegović – received death sentences after a trial that was held in August 1949 in Sarajevo.