Islamabad -- - Pakistani police fired tear gas at thousands of protesters as they tried to march toward the prime minister's home in the capital on Saturday, blanketing the route with clouds of caustic smoke and scattering demonstrators. Both Khan and Qadri, a dual Pakistani-Canadian citizen with a wide following, also demand reforms in Pakistan's electoral system to prevent future voter fraud. Riot police initially showed restraint to Saturday's march but when the crowd started removing shipping containers used as barricades, they fired salvos of tear gas canisters that forced the crowds back.