Followers of the Shi'ite Houthi movement flee as riot police use water canons and tear gas to disperse them along a main road leading to the airport in Sanaa September 7, 2014. Protesters from the Shi'ite Muslim group the Houthis cut off the road between the capital and Yemen's main airport while warplanes bombed Houthi rebel positions in the north on Sunday in a sharp escalation of weeks of tensions with the government. REUTERS/Khaled Abdullah (YEMEN - Tags: POLITICS CIVIL UNREST)