Pakistan celebrates independence amid security fears and political concerns. Pakistan celebrated 60 years of independence from British rule on Tuesday (August 14) with flag-raising ceremonies and fireworks but political troubles for a pro-U.S. president and fears of militant violence subdued festivities in several cities. President Pervez Musharraf faces one of his toughest periods since taking power in a 1999 coup, with growing political opposition to his attempt to win a second term and rising Islamist violence that has worried his ally, the United States. Opposition leaders from major political parties rallied in Rawalpindi, the garrison city adjoining capital Islamabad, calling upon Musharraf to step down and clear the way for a democratic government to take over. They appealed to the crowd of several thousand political workers to gear up for elections to oust the military government which they accused of being a "puppet" of the United States. Former test cricketer Imran Khan told the chanting, flag-waving crowd, Pakistan hadn't as a nation lived up to the dreams of Allama Iqbal, a national poet, or the struggle of Quaid-e-Azam, the founder of Pakistan. But he said "today we see a new Pakistan emerging before our eyes." Khan, leader of the Movement for Justice party, is a fervent critic of Musharraf's policies, especially his support for the United States' war against terrorism. Some U.S. politicians recently said the United States must be willing to strike al-Qaeda targets in Pakistan even without Islamabad's permission -- drawing rebuke in the country. Pakistan's Prime Minister Shaukat Aziz vowed on Tuesday to stop any "foreign power" from violating the country's borders, in an apparent reference to statements from U.S. politicians doubting whether Pakistan was making progress against militants. In Islamabad, which in past years would have been decked out with flags and illuminations, Independence Day was a low key affair due to security fears.