Chamran was one of the senior members of the Freedom Movement led by Mehdi Bazargan in the 1960s. He was part of the radical external wing together with Ebrahim Yazdi, Sadegh Ghotbzadeh and Ali Shariati.Following graduation, Chamran went to Cuba to receive military training. In December 1963, he along with Ghotbzadeh and Yazdi left the US for Egypt where he was trained in guerilla warfare.