MIRANSHAH ? (UPDATE) Suspected US missiles killed five militants in Pakistan's Al-Qaeda-infested tribal belt on Thursday not far from where 30,000 troops are battling a major anti-Taliban offensive.

The attack, which Pakistani officials said was carried out by a US drone, targeted a house in North Waziristan, where Washington says Islamist militants fighting against 100,000 US and NATO troops in Afghanistan are hiding.

"It was a US drone attack which targeted a compound of a local tribesman, Musharraf Gul, in Norak village, killing four militants and wounding three others," a senior security official in the area told AFP.

Two missiles were fired from a US drone at 1:30 a.m. (2030 GMT Wednesday).

Another security official confirmed the attack and said "Taliban rebels were using the compound."

"It is not clear if there was any high-value target," the official said, adding: "We also do not know yet the identity of the militants."

Pakistani officials said later that five militants died.

Although Pakistan opposes US drone attacks on its soil as a violation of sovereignty, the government's public condemnation of the strikes has subsided since a US missile killed Taliban warlord Baitullah Mehsud in August.

Around 60 US attacks have killed more than 580 people since August 2008, fanning anti-American sentiment in nuclear-armed Pakistan, where around 2,400 people have died in a wave of militant attacks since July 2007.

The US military does not, as a rule, confirm drone attacks, but its armed forces and the Central Intelligence Agency operating in Afghanistan are the only forces that deploy pilot-less drones in the region.

Thursday's strike comes with around 30,000 Pakistani troops, backed by warplanes and attack helicopters, pressing a major offensive against the Tehreek-e-Taliban Pakistan (TTP) networks in neighboring South Waziristan.

Pakistan vowed to crush TTP strongholds in South Waziristan, holding the umbrella organization responsible for a surge in militant attacks and bombings targeting civilians and security personnel around the country.

Pakistan launched its three-pronged offensive on October 17 and the military has claimed a string of successes, capturing TTP-held towns and villages, currently laying siege to Mehsud's once operational base of Ladha.

The military provides the only regular information coming from the frontlines. None of the details can be verified because communication lines are down and journalists and aid workers barred from the area.

So far, the military says more than 390 militants and 37 troops have been killed since the offensive began -- far fewer military losses than in previous offensives into South Waziristan that ended with controversial peace deals.

The military Wednesday reported "intense" street fighting in Ladha and that it had captured a major part of Sararogha, once notorious as the operational centre of Mehsud before his killing in an August 5 drone attack.

Although South Waziristan is the focus of Pakistan's current offensive, Islamist militants are embedded in large swathes of the mountainous northwest and have recently stepped up attacks in other tribal districts.

Islamist militants on Thursday blew up a second girls' school in less than a week in the lawless district of Khyber, on the main supply line for US and NATO troops fighting in landlocked Afghanistan, local officials said.

"Militants used 25 to 30 kilograms (55 to 66 pounds) of explosives to blow up the two-storey school on the outskirts of Bara town," local administration official Farooq Khan told AFP.

Khan said the school had 26 rooms in all, including a science laboratory, adding that the explosion completely destroyed eight rooms.