Pakistan's cricketer-turned-politician Imran Khan was placed under house arrest while several key opposition figures and lawyers were detained and a media office raided as part of the crackdown by the government after imposition of emergency.Lawyers, the judiciary and the media were among those targeted in the crackdown that began shortly after the beleaguered President Pervez Musharraf suspended the Constitution and declared emergency yesterday, citing threats posed to Pakistan's stability by judicial activism and growing extremism.Khan, the leader of the Tehreek-e-Insaf and an outspoken critic of Musharraf, was placed under house arrest at Banigala, near the national capital, by some 30 plainclothes policemen who surrounded his residence."Yes, I'm under house arrest," he told The Sunday Telegraph before his phone was abruptly cut off. Khan had accused the General of committing treason and said he was "punishable by death" for this.Besides Imran Khan, rights activist Asma Jahangir, the Chairperson of the Human Rights Commission of Pakistan, exiled former Premier Nawaz Sharif's PML-N leader Khawaja Asif, Opposition leaders Mehmood Khan Achakzai and Qadir Magsi, Supreme Court Bar Association President Aitzaz Ahsan and senior lawyers like Munir A Malik, Ali Ahmad Kurd and Tariq Mehmood were either detained or placed under house arrest.Ahsan and Kurd had represented ousted Chief Justice Iftikhar Muhammad Chaudhry when Musharraf first tried to dismiss him in March.Meanwhile, the office of Aaj TV channel in Islamabad was raided early this morning by officials who tried to seize live broadcast equipment.