Pakistan's military says air strikes have killed 20 suspected fighters in the northwestern tribal region of North Waziristan near the Afghan border.

In a statement on Saturday, the army said the strikes killed fighters in the Datta Khel area.

"At least 20 terrorists were killed in aerial strikes," the military said in a statement, without giving the identity of those killed or who they fought for.

No group said it had been hit, but the area is a stronghold of both the Tehreek-e-Taliban Pakistan (TTP), or the Pakistani Taliban, and al-Qaeda-linked foreign fighters.

The conflict zone is off-limits to journalists, making it difficult to independently verify the number and identity of those killed.

The air strikes were part of Operation Zarb-e-Azb that was launched in June last year against the TTP and other armed groups in the area. Tens of thousands of soldiers have been involved.

 

North Waziristan had been considered the headquarters of the Pakistani Taliban until last summer.

Al Jazeera's Kamal Hyder, reporting from Taxila, just outside the capital Islamabad, said the military was "determined" to put the TTP on the back foot, but it was a difficult process that had taken nearly a year.

"It is an operation you can not put a timeline on," he said.

In the year since the launch of Zarb-e-Azb, "so far, 2,763 terrorists [have been] killed [and] 837 hideouts destroyed", Major-General Asim Bajwa, Pakistan military spokesperson, said on Twitter.

At least "218 hardcore terrorists" have been killed and 347 officers and soldiers have lost their lives, he said.

Bajwa said the operation had now moved to the last few pockets close to the Pakistan-Afghanistan border.

Attack in Karachi

In a separate development, Pakistani police said on Saturday it had foiled an attack on a senior counterterrorism official and killed four fighters in the southern port city of Karachi.

It was the second attempt on Rao Anwar in little over a month. He survived a gun and grenade attack in early May in which five of the attackers were killed.

Victims of Karachi's violence talk to Al Jazeera

Anwar was also attacked by a suicide bomber in April 2012 while travelling home from his office. Four of his security personnel were killed in that incident.

As the top counterterrorism police officer in Karachi, dozens of Pakistani Taliban fighters have been killed in operations under his command in the past few months, according to local officials.

"Militants started chasing me in a vehicle and a motorbike as I left home with a police escort," Anwar told AFP news agency.

He said the fighters opened fire as police intercepted the car and bike. The police also retaliated, killing one of the assailants on the spot.

He said the three others ran away but police killed them later in an exchange of fire.

Najeeb Khan, another senior police official, confirmed the incident and said the fighters - who belonged to the TTP - were wanted for several attacks on law-enforcement agencies in Karachi.

Source: Al Jazeera and agencies