Pakistani fighter jets launched air strikes Sunday against militant hideouts in the country's troubled northwest, killing at least 80 insurgents including those linked to a brazen attack on Karachi airport, the military said.

But local security officials put the death toll far higher, saying that about 150 militants died in the air strikes, which primarily targeted Uzbek fighters in a remote area of tribal North Waziristan.

Among the dead were insurgents linked to last Monday's all-night siege of Karachi airport that killed 38 people, including 10 attackers, and all but destroyed a tentative peace process between the Pakistani Taliban (TTP) and the government.

One official said the alleged Uzbek mastermind of the Karachi attack had been killed in the strikes.

The military assault targeted the mountainous Dehgan area, some 25 kilometres (16 miles) west of the main town of Miranshah in North Waziristan, a stronghold for Taliban and Al-Qaeda-linked militants on the border with Afghanistan.

"Today at about 0130 hours (2030 GMT), a number of terrorist hideouts in Dehgan, Datta Khel in North Waziristan were targeted by jet aircraft. The number of terrorists killed in early morning strikes has risen to 80, mostly Uzbeks," a military statement said.

"There were confirmed reports of presence of foreign and local terrorists in these hideouts who were linked to the planning of the Karachi airport attack."

Local security officials in Miranshah, who spoke to AFP on the condition of anonymity, put the death toll far higher than the official toll.

"Up to 150 people were killed during the strikes early Sunday. These strikes were carried out based on confirmed reports about the presence of Uzbek and other militants in the area," an intelligence official said.

Another security official said that "the number of the killed people was even more than 150".

The Pakistan military has not confirmed the higher figure.

However, the military statement said "an ammunition dump had also been destroyed during the strikes and that further details would follow", suggesting the death toll could rise.

A military official in Miranshah said the alleged mastermind of the Karachi attack was among the dead. "Abu Abdul Rehman Almani, who was mastermind of attack on Karachi airport, and several other commanders have been killed in the strikes," the official told AFP.

Taliban spokesman Shahidullah Shahid, in a an e-mail to media vowed to avenge these attacks, but was not immediately available to provide further details.

But in a blow to the government's bid to clear militants from North Waziristan a local tribal jirga chief, who had been given a 15-day deadline by the government to expel foreign militants from the troubled region, said the air strikes had made it impossible for him to mediate with the fighters.

"We were going to organise a meeting of jirga today (Sunday) to decide the fate of Uzbeks but these air strikes have spoiled the environment," jirga chief Sher Mohammed told AFP.

"Now we are unable to carry on our work in these circumstances."

In a separate incident, three security officials were injured in an IED attack on a security convoy in the town of Mir Ali, 25 kilometres east of Miranshah. Military helicopters responded by shelling suspected hideouts in the town.

- Pakistan under pressure -

Hordes of foreign militants, including Chechens, Uzbeks, Turkmen, Tajiks and Uighurs, were drawn to North Waziristan in the early 2000s, lured by the fiery rhetoric of Osama bin Laden and the chance to fight "infidel" forces in Afghanistan.

But many of them have been slipping away amid long-running rumours of a military operation, with official estimates suggesting an exodus of some 60,000 people from the region since May.

Pressure has been mounting on the Pakistani government to launch a ground offensive in the Taliban-infested North Waziristan, one of seven tribal districts along the border. But authorities have held back from a final push -- possibly fearing the blowback in Pakistan's major cities such as Karachi.

The past week, however, has seen a significant increase in air strikes and renewed drone attacks.

Following the brazen assault in Karachi, the US carried out two drone strikes in North Waziristan on Wednesday -- the first time the controversial programme has been used this year -- and Pakistani air force jets pounded suspected militant hideouts, leaving at least 25 dead.

Washington reportedly suspended its drone programme in December to give Islamabad time to pursue peace talks with the TTP aimed at ending a seven-year insurgency that has claimed thousands of lives.

The dialogue resulted in a month-long ceasefire between March and April, but later broke down, with Pakistan resuming air strikes on suspected militant hideouts in the tribal areas.

The army was widely seen as being opposed to the dialogue because of the heavy casualties it has sustained at the hands of the TTP, which views them as a mercenary force serving foreign interests.

But following the breakdown of the talks and the Karachi attack, observers believe both civil and military authorities are converging on the need for more concerted action.

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