Imams held in Pakistan crackdown

Mosques and madrassas are being put under close watch

Police in the Pakistani province of Punjab have briefly detained over 100 prayer leaders for breaking a law on broadcasting sermons over loudspeakers.

The arrests came amid a crackdown on suspected religious extremists in Pakistan, following bombings in London.

Police said the government had ordered strict observance of a law which says loudspeakers must be used only for the call to prayers, and not for sermons.

Sermons broadcast on loudspeakers are accused of helping fan sectarian hate.

It was the first time the government had issued instructions for a strict adherence to the law Punjab police official

All the clerics detained late on Friday, mostly in Punjab's volatile south, were freed on bail after appearing in local courts on Saturday.

Formal charges are expected to be brought at a later stage.

The BBC's Aamer Ahmed Khan says sermons played over mosque loudspeakers frequently exacerbate Sunni-Shia tensions in southern Punjab, which has a long history of sectarian violence.

He says the enforcement of the loudspeaker law could be very significant in helping curtail hate campaigns propagated from certain mosques - if measures are implemented nationwide over a sustained period of time.

London bombs

The prayer leaders' arrests followed a day of muted protest across Pakistan by religious activists angered by raids on religious schools, or madrassas, and the detention of at least 200 suspected extremists.

MUSHARRAF'S NEW MEASURES Banned groups not allowed to operate under new names No public displays of unauthorised weapons Clampdown on inflammatory material, including audio, video tapes and their publishers and distributors Militant groups not allowed to collect funds Monitoring hate sermons from mosques All madrassas registered by December 2005 Musharraf looks to West Why a new crackdown? Press split on crackdown

Pakistan is under pressure to take action against extremists, after it emerged that two London bombers travelled to the country last year.

Both were Britons of Pakistani descent. Exactly what they did during their trip has not been established, but security officials want to know if they met militants.

The family of one has said he visited a madrassa. Some madrassas are accused of having links with militant groups.

On Thursday President Pervez Musharraf defended his crackdown in a televised address to the nation.

He called for Pakistanis to join a holy war on extremists and announced all religious schools would have to register with the government by December.

But he also urged Britain to do more to tackle its own militancy threat.

Religious activists are incensed by raids on their schools

Observers say it is still too early to tell what long-term effect the latest measures announced in Pakistan will have.

Crackdowns in 2000 and 2002 foundered after banned groups re-emerged with new names.

Police in Pakistan have yet to arrest anyone who has a direct link to the London bombings, security sources have told the BBC.

The 7 July blast killed 56 people, four of them suicide bombers.