A security professional in Kabul familiar with the operation said the 3,000-strong force was set up in 2002 to capture targets for CIA interrogation. A former U.S. intelligence official said members of the covert Afghan force are used for surveillance and long-range reconnaissance and some have trained at CIA facilities in the U.S.
The sources spoke Wednesday on condition of anonymity to discuss matters of intelligence.
The force, called the Counterterrorist Pursuit Team, was described in a new book by Bob Woodward, "Obama's Wars." The paramilitaries, designed after U.S. commando teams, operate in violence-wracked provinces including Kandahar, Khost, Paktia and Paktika, as well as the capital, Kabul, the security professional said.
Woodward also reports the units conduct covert operations inside neighboring Pakistan's lawless border areas as part of a campaign against al Qaeda and Taliban havens there. Pakistan does not permit U.S. special operations forces to enter the area, except for limited training missions. The alleged use of Afghan paramilitaries to carry out spying activities will likely inflame already frayed political relations between Afghanistan and Pakistan.
The U.S. military, including special operations forces, has been working with the CIA in an intensified crackdown against militants on both sides of the Afghan and Pakistan border. Drone strikes run by the CIA are at their highest level yet against Afghan Taliban, Haqqani and al Qaeda leaders in Pakistan, while U.S. special operations forces have been staging combined raids with Afghan army special forces against the midlevel leadership that operates on the Afghan side.
It's unclear whether the CIA-run Afghan paramilitary units also work alongside U.S. special operations forces, but the security professional said the units do coordinate their operations with NATO.
The former official said the Afghan force became the focus of an internal turf battle last year between CIA and military officials over who would control its operations. The CIA remained the lead agency, the former official said.
The U.S. official said the force is highly trained and its raids have made "major contributions to stability and security."
The force's Kandahar branch was accused of killing the Kandahar police chief in 2009 over a dispute when one of its own members was arrested. The U.S. official said the incident had been "reviewed fully."
The official added that the incident was "not typical" of the force and that the paramilitaries were reacting to what they viewed as the "unfair arrest of one their people by one of their rivals."
According to Woodward's book, Obama aides were deeply divided over the war in Afghanistan even as the president agreed to triple troop levels there. Obama's top White House adviser on Afghanistan and his special envoy for the region are described as believing the strategy will not work.