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The Lindt Cafe in Martin Place, Sydney, Australia, was the target of a siege carried out by Man Haron Monis on December 15-16, 2014. Monis, a self-proclaimed Muslim cleric, held 18 people hostage inside the cafe for 16 hours, demanding that an Islamic State (ISIS) flag be displayed on the Sydney Opera House and that he be allowed to speak with the Prime Minister of Australia.