At least two dozen militants were killed by the Pakistani security forces in the Mohmand tribal region on Tuesday, an official said.
Jet aircraft attacked militant positions in Kandharo village before ground troops moved in to clear the area, which is located close to the Afghan border.
"The airstrike inflicted heavy casualties on the insurgents. At least 24 militants were confirmed killed in the offensive," an official of the Frontier Corps paramilitary force said requesting anonymity.
Several other rebels were also injured, he said without giving any figures. The casualty toll could not be confirmed independently.
"Our soldiers have secured vast swathes of land after the assault," the official said.
Mohmand borders the Bajaur tribal district where government troops, backed by tanks and helicopter gunships, began a major offensive in August against Al Qaeda and Taliban militants, who crossed into the region from Afghanistan to escape the coalition forces.
Militant activity in Mohmand surged after the Bajaur operation in which the military had so far claimed to have killed more than 1,500 fighters.
The US and other western forces hailed the intense offensive, saying it helped reduce cross-border attacks on the international troops fighting the Taliban.
Tuesday's assault in Mohmand came as US Central Command chief General David Petraeus arrived in Islamabad for talks with Pakistani President Asif Ali Zardari, Prime Minister Yousaf Raza Gilani and Chief of the Army Staff General Ashfaq Parvez Kayani.
Petraeus said he had "very good" meetings and both sides discussed actions taken by Pakistan in the aftermath of the Nov 26 Mumbai attacks as well as the country's counter-terrorism initiatives in the northwest.
"It is clearly in the interest of all countries involved that Pakistan succeeds in dealing with its internal problems," Petraeus told reporters.
The US general said Washington would increase its support for Pakistan to fight militancy in its northwestern regions, adding that more focus would be put on coordination between military commanders on both sides of the Afghan border.
Petraeus, who came to Pakistan hours before the inauguration of Barack Obama in Washington, hoped that "the new administration in the US will bring progress in our mutual efforts to counter extremism".
He was due to fly to Kabul in the evening for security talks with Afghan officials.