Pakistan has declared a high alert in the twin cities of Islamabad and Rawalpindi as well as in all cantonment areas across the country in the wake of suicide attacks in North West Frontier Province and threats from Al Qaeda [Images] and local Taliban who have vowed to retaliate against the government's Lal Masjid operation.

Heavy deployment of rangers has been made at the Margallas to avoid any terrorist attack from the hillside at key government installations and foreign embassies in Islamabad, the Dawn reported on Monday, quoting sources as saying.

Security at sensitive installations, including places of worship, airports, government offices and international missions, has been beefed up. Public areas like shopping centres, movie theatres, parks and restaurants have also been put under surveillance.

Apart from placing the police headquarters and two state-run hospitals in the twin cities on high alert, 12 sensitive areas in Rawalpindi have been declared red zone.

A large number of police personnel have been deployed at all entry and exit points of the twin cities to avoid entrance of any miscreants, and the security forces have set up pickets at various points here to check people coming from outside, particularly from the NWFP.

Similarly, all the cantonment areas across the Islamic nation have been put on high alert.

The government has also advised foreign nationals in the country to restrict their movements and avoid going to public places and gatherings without adequate security, the sources said.