This report was filed by CBS News' Farhan Bokhari in Islamabad.
Pakistan, the U.S., and other NATO member countries have had a quiet, unwritten agreement for the past three to five years to allow the CIA to fly unmanned drones out of remote airstrips in the Pakistan-Afghanistan border region, a senior military official from a NATO country confirmed to CBS News on Thursday.
In the past week, speculation has mounted over the extent to which Pakistan was aware of such flights, amid evidence that at least some of the drones were being launched from airstrips in remote Pakistani regions.
The issue is potentially explosive for Pakistan — a country that has been an ally to the U.S. in Washington's fight against Islamic extremism, but has routinely protested the drone strikes on suspected Taliban and al Qaeda militants in Pakistan's border region, which have also caused numerous civilian casualties.
On Tuesday, The Times newspaper of London reported that the drone flights were originating from an airstrip known as Shamsi in southwest Pakistan. At the same time, The NEWS, a Pakistani English language newspaper, printed what it said were images of that site showing three predator drones parked on a runway.
On Thursday, the Islamabad-based NATO military official, who spoke to CBS News on condition of anonymity, said the U.S., Pakistan and NATO had all collaborated in the use of remote locations in Pakistan and Afghanistan to operate the drones.
"There is no single site you can name. We are looking at different locations both in Pakistan and Afghanistan," said the official. "If the Shamsi base has been found to be a home for the drones, that is not the only location."
A NATO country diplomat stationed in Islamabad, who also spoke to CBS News on condition of anonymity, confirmed the information given by the military official. "There is no one location. The locations keep on changing in both countries (Pakistan and Afghanistan). But yes, there are drones flying from locations in both these countries," said the diplomat.
Pakistani opposition politicians have repeatedly denounced their own government for its support of the U.S.-led war against militants, and called for an end to all cooperation with Washington.
However, a Pakistani government minister told CBS News on Thursday there was no question of ending Islamabad's support for Washington, especially given Pakistan's weak economy which, has made it rely on the U.S. for badly needed financial aid.
"The U.S. holds a vital lifeline for Pakistan. How can we move to cut that off ourselves," asked the minister, who also asked not to be named due to the sensitive nature of the matter.
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