The U.S Secretary of State Hillary Clinton has questioned Pakistan's failure to capture senior al-Qaeda leaders. Mrs. Clinton said in an interview with journalists in Lahore that she found it hard to believe that nobody in the government knew where they are. She also challenged opposition to a U.S aid package, criticising Pakistan's investment levels and taxation system. <br/>Mrs. Clinton has been in Pakistan for trying to strengthen ties with the government, shore up the fight against militants and tackle rising anti-US feelings among the Pakistani people. <br/>Mrs. Clinton will now head to the Middle East to try to kick-start the Israel-Palestinian peace process. <br/>