The PLO took advantage of its control of southern Lebanon in order to launch Katyusha rocket attacks at Galilee villages and execute terror attacks on the northern border. At the beginning of the 1970s the Palestinian terror organizations, headed by the PLO and the Popular Front for the Liberation of Palestine waged an international terror campaign against Israelis, primarily in Europe. In an attempt to publicize the Palestinian cause, frustrated Palestinian guerrilla groups in Lebanon attacked Israeli civilian 'targets' like schools, buses and apartment blocks, with occasional attacks abroad—for example, at embassies or airports—and with the hijacking of airliners. The peak of the Palestinian terrorism wave against Israelis occurred in 1972 and took form in several acts of terrorism, most prominently the Sabena Flight 572 hijacking, the Lod Airport massacre and the Munich massacre.