Pakistani Shi'ite Muslims shout slogans as they burn the U.S. and Israeli flag during the Shi'ite Chelum religious commemoration in Karachi February 5, 2010. Shi'ite Muslims commemorate Chelum, or Arbain, to mark the end of a 40-day period of mourning for the Prophet Mohammad's grandson who died in AD 680. REUTERS/Athar Hussain (PAKISTAN - Tags: POLITICS CIVIL UNREST RELIGION)