World News - Pakistan says U.S. drones in its air space will be shot down ISLAMABAD -- Pakistan will shoot down any U.S. drone that intrudes its air space per new directives, a senior Pakistani official told NBC News on Saturday. Asghar Achakzai / AFP - Getty Images file Pakistani security personnel examine a crashed US surveillance drone inside Pakistan in August. According to the new Pakistani defense policy, "Any object entering into our air space, including U.S. drones, will be treated as hostile and be shot down," a senior Pakistani military official told NBC News. The policy change comes just weeks after a deadly NATO attack on Pakistani military checkpoints accidentally killed 24 Pakistani soldiers, prompting Pakistani officials to order all U.S. personnel out of a remote airfield in Pakistan. Pakistan told the U.S. to vacate Shamsi Air Base by December 11. A senior military official from Quetta, Pakistan, confirmed to NBC News on Saturday that the evacuation of the base, used for staging classified drone flights directed against militants, â€œwill be completed tomorrow,â€ according to NBCâ€™s Fakhar ur Rehman. Pakistan's Frontier Corps security forces took control of the base Saturday evening after most U.S. military personnel left, Xinhua news agency reported. Civil aviation officials also moved in Saturday, Xinhua said. Pakistani Military Chief Gen Ashfaq Pervez Kayani had issued multiple directives since the Nov. 26 NATO attack, which included orders to shoot down U.S. drones, senior military officials confirmed to NBC News on Saturday. It was unclear Saturday whether orders to fire upon incoming U.S. drones was part of the initial orders. supporters of opposition political party Pakistan Tehrik-e-Insaf (Movement of Justice) carry a mock US drone as they listen to a speech by the party founder Imran Khan, during a protest rally against the United States drones attacks. The Pakistani airbase had been used by U.S. forces, including the CIA, to stage elements of a clandestine U.S. counter-terrorism operation to attack militants linked to al-Qaida, the Taliban and Pakistan's home-grown Haqqani network, using unmanned drone aircraft armed with missiles. President Barack Obama stepped up the drone campaign after he took office. U.S. officials say it has produced major successes in decimating the central leadership of al-Qaida and putting associated militant groups on the defensive. Since 2004, U.S. drones have carried out more than 300 attacks inside Pakistan. Pakistani authorities started threatening U.S. personnel with eviction from the Shamsi base in the wake of the raid last May in which U.S. commandos killed Osama bin Laden at his hide-out near Islamabad without notifying Pakistani officials in advance.