Pakistan has launched a large-scale military operation in the North Waziristan region today against Taliban and Uzbek militants who have long used the ethnic Pashtun region on the Afghan border as a base.

The assault essentially ended Pakistan's chances of further dialogue with the militants, who have been working for years to overthrow the Pakistani government and establish a Sharia-based caliphate, resulting in the deaths of tens of thousands of civilian and army forces in the area.

"Our valiant armed forces have been tasked to eliminate these terrorists regardless of hue and color, along with their sanctuaries," the Parkistan army said in a statement. "With the support of the entire nation, and in coordination with other state institutions and law enforcement agencies, these enemies of the state will be denied space anywhere across the country."

The operation, involving troops on the ground, artillery and helicopter gunships, follows last week's Karachi airport attack, which killed 38 people. It was also announced hours after Pakistani air strikes targeting militant hideouts killed at least 80 insurgents.

Security has been ramped up in major cities across Pakistan following recent militant assaults on Karachi. Credit: Radio Free Europe/Radio Liberty

Around 40,000 troops have been deployed for the operation, adding to the 40,000 already present in the region, a military official told Reuters.

It is not known whether civilians have been harmed or killed, but many are fleeing the mountainous region to other parts of Pakistan in anticipation of further violence.

Pakistani authorities, fearing that the militants may try to escape along with civilians, have sealed off the border with neighboring Afghanistan and imposed a curfew in the area.

Thousands of people have begun to flee Pakistan’s North Waziristan tribal district. Credit: Radio Free Europe/Radio Liberty

There was no word today from Pakistani Prime Minister Nawaz Sharif, who had previously refrained from direct military warfare with the Pakistani Taliban, attempting instead to engage in a policy of negotiation.

It was left to the country's defense minister to defend Pakistan's recent decision to establish military control over the country's north, despite fears that the operation will spark a violent and bloody backlash.

"We as a government tried our level best to resolve this crisis through dialogue," the defense ministry said in a statement. "We were frustrated through attacks on innocent Pakistanis and damage to national assets.

"This operation will continue until the surrender or elimination of the enemy."

The Islamic Movement of Uzbekistan (IMU) and the Pakistani Taliban's joint claims of responsibility for last week's attack on Karachi airport seemed to mark a turning point for Pakistanis, prompting renewed US and Pakistani drone strikes against militant positions.

Militants disguised as police stormed Pakistan’s Jinnah International Airport in Karachi on June 8. Credit: Radio Free Europe/Radio Liberty

Most of those who died in the air strikes on Sunday were Uzbek militants, Pakistani military officials told the Associated Press.

The IMU, is a militant group who initially sought to overthrow the Uzbek government and set up an Islamic state under Sharia, but later expanded its ambitions to encompass Central Asia as a whole.