Pakistanis flee army offensive near Afghan border
The rest of the story is that the extremist militants also know well in advance when and where these punitive show expeditions are coming, and they get out of the way too.
At least 20,000 people have fled fierce fighting between troops and militants in the Pakistani tribal region of Mohmand, officials and witnesses say.
Many of the displaced are sheltering in temporary camps, the authorities add.
Troops have been using helicopter gunships and heavy weapons to pound suspected militant positions for a week, according to residents.
Mohmand, on the border with Afghanistan, has long served as a sanctuary for the Taliban and al-Qaeda.
“We are targeting militant hideouts there,” military spokesman Maj-Gen Athar Abbas confirmed.
The army told the BBC that 60 to 70 militants had been killed in what it calls a search and clearance operation.
There is no independent confirmation of the casualty figures - independent media have no access to the area.