Tens of thousands of Hamas loyalists gathered in a Gaza City arena on Sunday to celebrate 21 years since the terror group's day of establishment. The rally is another show of strength by the terrorist group that has ruled Gaza since a violent takeover in June 2007. The arena, which can hold about 150,000 people, was full, with more people spilling out into the streets. Many Hamas supporters wore baseball caps in the movement's Islamic green. Thousands of policemen were organizing traffic on roads decked with green Hamas flags while plainclothes policemen patrolled the area. Senior Hamas leaders are expected to lay out the future of the Egyptian-mediate truce with Israel and its relations with Fatah.