The authorities in Pakistan have introduced new security measures around non-Muslim places of worship, fearing fresh attacks from Islamic militants.

Police rounded up a number of men in Karachi

The move follows the arrest of a number of militants in the southern city of Karachi, some of whom allegedly had in their possession maps and plans showing places of worship and foreign establishments.

Those in detention were arrested as part of a recent crackdown against militants suspected of involvement in the bombing of the US consulate in June and an attempt to assassinate President Musharraf.

A number of foreign targets as well as Christian establishments have been attacked in the past year, leaving dozens of people dead.

'Attacks planned'

Police and Interior Ministry officials told the Associated Press that the maps showed exit and entry points for Christian sites in Karachi.

Two men, suspected of belonging to splinter group of the militant Harakat ul-Mujahideen, were allegedly in the process of planning an attack when they were arrested, the un-named officials said.

However, senior investigator Manzoor Mughal told the French news agency that the maps had not yet been deciphered, and it was not clear what was being planned.

Reports from other parts of Pakistan said that security around churches - already tight - had been stepped up even further.

In Punjab province, signs had been removed identifying churches set up in private homes, and sandbags had been erected around some church buildings.

Foreign targets

There have been several attacks on foreign targets in Pakistan including:

• A grenade attack on a church in Islamabad's diplomatic quarter in March, which killed five people.
• A suicide attack on a navy bus in Karachi in May which killed 14 people.
• A car bomb at the US consulate in Karachi in June, which killed 12 people.
• An attack on a missionary school near Islamabad in August, which killed six people.

The Pakistani authorities have blamed the attacks on members of militant Islamic groups, angered by Pakistan's decision to support the US-led war in Afghanistan.