Iran's Supreme Leader Ayatollah Ali Khamenei wept while leading mourners in prayer for the funeral Monday of slain military commander Qassem Soleimani, whose death in a U.S. drone strike has caused a huge outpouring of national grief. Iranians poured on to the streets of the capital Tehran to bid farewell to the commander of the Quds Force, the unit in charge of foreign operations of Iran's Revolutionary Guards.