The air strikes in North Waziristan tribal region on Tuesday followed two major Taliban attacks on military targets in as many days.
"Most of [the] terrorists killed are foreign fighters including 33 Uzbeks and three Germans," the source told AFP.
Uzbeks, many affiliated with the the Al-Qaeda-linked Islamic Movement of Uzbekistan, make up one of the largest groups of foreign fighters in Pakistan's tribal northwest.
There was no immediate confirmation from the countries concerned. Independent verification of casualties was not possible because media and aid workers are not allowed to visit the area.
The source added that Wali Muhammad, a Pakistani Taliban commander and trainer of suicide bombers, was among the dead. This was confirmed by a senior militant source.
Tuesday's operation was one of the heaviest bombardments in recent years in North Waziristan, a key stronghold of militants linked to the Taliban and Al-Qaeda.
Officials said some of those killed were linked to an attack on Sunday on paramilitary troops in the northwestern city of Bannu that killed 26, and a double suicide bombing on a church in September that killed more than 80.
Another military official said a few families had fled the fighting and moved out of the tribal areas but so far there has been no mass migration from the area.
The government officials said that around 500 families fled to Bannu district from North Waziristan after the bombardment.
"Some 500 families from Mir Ali sub-division of North Waziristan have migrated to Bannu. They are living with the local host tribes of Mamashkhel and Bakakhel in Bannu," said Arshad Khan, head of the Fata Disaster Management Authority (FDMA).