WASHINGTON -- With Pakistan reeling from a terrorist attack that killed 141 people, mostly children, opposition leader Imran Khan on Wednesday declared an end to protests that have overtaken the capital of Islamabad for four months. Khan, who leads the Pakistan Tehreek-e-Insaf Party (PTI), launched countrywide sit-in protests on Aug. 14 in Lahore, demanding the ouster of Prime Minister Nawaz Sharif amid allegations of rigging last year's general elections.