The UN mediator on Palestine Folke Bernadotte reported in September 1948 that Palestinian flight, "resulted from panic created by fighting in their communities, by rumours concerning real or alleged acts of terrorism, or expulsion". United Nations observers, who had been dispatched to monitor how the partition plan, reported in October that Israeli policy was that of "uprooting Arabs from their native villages in Palestine by force or threat". In the Negev the clearing was more complete because "the OC, Allon, was known to want "Arab-clean" areas along his line of advance" and "his subordinates usually acted in accordance" and the inhabitants were almost uniformly Muslim. In the Galilee pocket, for various reasons, about 30–50 per cent of the inhabitants stayed. More specifically regarding the causes of the exodus Morris says: "Both commanders were clearly bent on driving out the population in the area they were conquering," and "Many, perhaps most, [Arabs] expected to be driven out, or worse. Hence, when the offensives were unleashed, there was a 'coalescence' of Jewish and Arab expectations, which led, especially in the south, to spontaneous flight by most of the inhabitants. And, on both fronts, IDF units 'nudged' Arabs into flight and expelled communities." The "Two-stage explanation" brought forth by Yoav Gelber synthetises the events of 1948 in distinguishing two phases in the exodus. Before the first truce (11 June – 8 July 1948), it explains the exodus as a result of the crumbling Arab social structure that was not ready to withstand a civil war, and justified Jewish military conduct. After the truce the IDF launched counter offensives against the invading forces. Gelber explains the exodus in this stage as a result of expulsions and massacres performed by the Israeli army during Operation Dani and the campaign in the Galilee and Negev. Gelber describes the exodus before July 1948 as being initially mainly due to the inability of the Palestinian social structure to withstand a state of war :  According to Efraim Karsh in April 1948 "some 100,000 Palestinians, mostly from the main urban centres of Jaffa, Haifa, and Jerusalem and from villages in the coastal plain, had gone. Within a month those numbers had nearly doubled; and by early June, ... some 390,000 Palestinians had left." 30,000 Arabs, mostly intellectuals and members of the social elite, had fled Palestine in the months following the approval of the partition plan, undermining the social infrastructure of Palestine.