20,000 Flee Pakistan's Border
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.
A local administration official, Roshan Khan Mehsud, told the BBC that civilians had been displaced from Safi, Pindiali and Baizai districts, close to the border with Afghanistan.
"Most people left the area due to fear of mines and other hazards, and we ourselves moved some of them for reasons of safety," he said.
The army had also sustained "some casualties", Mr Mehsud told the Associated Press news agency. There was no immediate word on this from the military.
Officials estimate the total number of displaced people at between 20,000 to 25,000.
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