In 1972, Öcalan was arrested after participating in a protest against the killing of Mahir Çayan. He was held at for seven months at Mamak Prison. In November 1973, the Ankara Democratic Association of Higher Education, ("Ankara Demokratik Yüksek Öğrenim Demeği," "ADYÖD") was founded and shortly after he was elected to join its board. In December 1974, "ADYÖD" was closed down. In 1975 Öcalan, together with Mazlum Doğan and published a political booklet which described the main aims for a "Revolution in Kurdistan". During meetings in Ankara between 1974 and 1975, Öcalan and others came to the conclusion that Kurdistan was a colony and preparations ought to be made for a revolution. The group decided to disperse into the different towns in Turkish Kurdistan in order to set up a base of supporters for an armed revolution. At the beginning, this idea had only a few supporters, but following a journey Öcalan made through the cities of Ağrı, Batman, Diyarbakır, Bingöl, Kars and Urfa in 1977, the group counted over 300 adherents and had organised about thirty armed militants.