Seven suspects, including the father of Pakistan’s nuclear programme, remain under investigation for allegedly selling nuclear secrets to Iran and Libya, and a decision on whether to put them on trial will only be made when the probe is complete, an official said.

Pakistani police have reportedly arrested at least 500 activists from the country’s three leading Islamic organisations in an attempt to prevent further protests against the ongoing US attacks on neighbouring Afghanistan.

Police today moved to block a major protest against the US-led air campaign in Afghanistan by barring the head of Pakistan’s largest Islamic party from travelling and arresting scores of militants.

Hardline Muslims are pushing for a nationwide strike to show their opposition to Pakistan's decision to co-operate with the United States.