 Complete the following phrase:  During the 1975-77 phase of the Lebanese Civil War, the al-Murabitoun militia forces were heavily committed in several battles and suffered considerable casualties, especially at the Battle of the Hotels in October 1975 where they engaged Christian Kataeb Regulatory Forces and Tigers Militia fighters, and later at the Spring Offensive held against East Beirut and Mount Lebanon in March 1976. They also took part on January 20 of that same year in the violent and controversial sieges of the Christian towns of Es-Saadiyat, Damour, and Jiyeh in the Iqlim al-Kharrub, on the side of PLO and Palestine Liberation Army PLA units to avenge the earlier 