Pakistani soldiers fought militants in a northwestern tribal region near the Afghan border, the military said Sunday. Eighteen people, including one soldier, died in the clash.

A military statement said some of the dead were women and children, while a military official told The AP that a majority of those killed were women and children who were believed to be members of the militants' families.

Fighting broke out late Saturday when the militants tried to flee in two vehicles while soldiers were searching houses near Miran Shah (search), the main town in North Waziristan, the army's Inter-Services Public Relations department said in a statement.

The drivers ignored an order to pull over. Instead, gunmen fired and lobbed grenades at the troops, killing one, said the statement issued in Rawalpindi (search), a city where the army is headquartered.

Soldiers fired back, destroying one of the vehicles with a rocket that ignited ammunition stocks inside. Four suspected militants, believed to be from Kazakhstan (search) or elsewhere in Central Asia, and their 12 local supporters were arrested.

The statement said several women and children were killed in the shootout.

But a military official in northwestern city of Peshawar, near the Afghan border, said on condition of anonymity that in fact a majority of the dead were women and children. The official said 15 women and children were killed, all believed to be members of the suspects' families.

The military statement said four Kazakh passports, an unspecified amount of ammunition, explosive material, detonators and instructions for making improvised explosive devices were seized from the scene.

Security officials have said hundreds of Arab, Central Asian and Afghan militants, allegedly linked to the Al Qaeda terrorist network, are in the North and South Waziristan tribal regions bordering Afghanistan. Army and paramilitary troops have carried out several operations to hunt down the fighters.

Pakistan, a key ally of the United States in the war on terror, has deployed thousands of troops to the border region.

On Friday, Pakistani troops found the bodies of 24 suspected Taliban militants who were killed in fighting with U.S. and Afghan soldiers. Pakistan said the fighting occurred on the Afghan side of the rugged border, which is not clearly marked.

Pakistan's military said it believed the fighters may have been trying to enter North Waziristan when they were killed. Afghan and U.S. officials say Taliban insurgents often stage attacks from Pakistani areas, though Pakistan denies it.