The Pakistan army said it had killed more than 35 militants but lost 15 of its men in fighting since Wednesday in South Waziristan, a rugged mountain territory bordering Afghanistan. It has reported three civilian deaths.

On Friday, the army pounded militants in the Shakai area, about 250 miles southwest of Islamabad and 11 miles west of the regional capital, Wana, where the flare up began this week.

Pakistan has said up to 600 foreign militants, including Arabs, Chechens and Uzbeks linked to Osama bin Laden's al-Qaeda network, have been hiding out in tribal areas close to the Afghan border protected by Pakistani tribesmen.

Many people, including women and children, walked for miles to safety after authorities ordered residents of Shakai to evacuate the battle zone, where government jets bombed houses where militants were thought to be holed up.

Intelligence officials said it appeared supporters of al-Qaeda were carrying out attacks in other parts of Pakistan in response to the army crackdown in the tribal region.

On Thursday, the army commander in the southern port city of Karachi narrowly survived an assassination attempt when suspected Islamic militants attacked his motorcade.

Ten people, including several soldiers, were killed in the attack, which came six months after two attempts to kill Pakistani President General Pervez Musharraf.

Nek Mohammed, a supporter of the foreign militants in South Waziristan, told the British Broadcasting Corp's Pashto-language service on Thursday that the attack in Karachi was a response to the military's operation on the border and more attacks were planned.