Violence has broken out at protests in Lahore and elsewhere in Pakistan against President Pervez Musharraf's imposition of emergency rule.

Lawyers staged rallies in a number of cities, including the capital Islamabad, against the sacking of top judges and restrictions on the judiciary.

The independent judiciary has been one of the main obstacles to Gen Musharraf. He reportedly feared it would declare his re-election as president illegal.

Political opponents, including the Islamist party Jamaat-e-Islami, have also staged protests against military rule, and say hundreds of activists have been arrested.

Pakistani police set up checkpoints and surrounded court buildings in an attempt to head off protests. The West has called the crackdown "disturbing".

In Karachi a lawyers' protest was broken up and demonstrators were bundled into waiting vans by plain-clothed police.

But as lawyers were taken away they signalled their defiance. "We will continue our fight, come what may," said one as he was bundled into a car.