This heavily-armed force is operated by Afghan personnel in small units called Counter- terrorism Pursuit Teams is quoted from a new book 'Obama's wars' by journalist Bob Woodward.
"Firing missiles from unmanned drones patrolling over Pakistan's turbulent northwest tribal region at a rate that has outstripped the Bush administration's record is bad enough and now to have brigade size paramilitary units operating inside Pakistan marks a significant expansion of the covert war that the Obama administration has waged there," the book claims.
The CIA directs and funds the force and recognised them as the best Afghan fighting force which has made major contributions to stability and security.
"The covert army captures and kills Taliban fighters and seeks support in Tribal areas," said Pentagon officials
The book also revealed the remarks of Obama, "We need to make clear to the people that the cancer is in Pakistan", pursuing the CIA to turn into classic old strategy of setting up of a lethal proxy unit.