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Gaddafi organized demonstrations and distributed posters criticizing the monarchy. In October 1961, he led a demonstration protesting Syria's secession from the United Arab Republic. During this they broke windows of a local hotel accused of serving alcohol. Catching the authorities' attention, they expelled his family from Sabha. Gaddafi moved to Misrata, there attending Misrata Secondary School. Maintaining his interest in Arab nationalist activism, he refused to join any of the banned political parties active in the city – including the Arab Nationalist Movement, the Arab Socialist Ba'ath Party, and the Muslim Brotherhood – claiming he rejected factionalism. He read voraciously on the subjects of Nasser and the French Revolution of 1789, as well as the works of Syrian political theorist Michel Aflaq and biographies of Abraham Lincoln, Sun Yat-sen, and Mustafa Kemal Atatürk.

While he was in secondary school, what sort of activism did Gaddafi support?
Arab nationalist activism