Riot police run after a supporter of Tahir ul-Qadri, Sufi cleric and leader of political party Pakistan Awami Tehreek (PAT), outside the parliament house as the supporters marched towards the prime minister's house in Islamabad August 30, 2014. Thousands of protesters massed outside the residence of Pakistani Prime Minister Nawaz Sharif on Saturday to demand he step down, after efforts to find a negotiated solution to the country's political crisis failed. REUTERS/Zohra Bensemra (PAKISTAN - Tags: POLITICS CIVIL UNREST)