During Israeli raids from 1968 to 1977, some of the Palestinian towns and camps in the area were totally leveled. According to estimations, by October 1977 about 300,000 refugees, mainly Shiite Muslims, fled South Lebanon.[citation needed] The PLO-Israeli conflict increased political tensions between Maronite Christians and Druze on the one hand and Muslims on the other, adding to the factors behind the 1975–1990 Lebanese Civil War.