NATO helicopters Wednesday violated Pakistan\'s airspace and intruded inside the volatile North Waziristan tribal region, which the U.S. and Afghan officials claim is the main base for al-Qaeda and Afghan Taliban, officials in the region said. The choppers entered Pakistani airspace from neighboring Afghanistan in the border area of Datta Khel, just few km from Miranshah, center of North Waziristan, they said. Local tribesmen also spotted the NATO helicopters at around 02: 00 p.m. local time, who they said had been flying for five minutes. They had arrived from Paktiya province. Officials said that Pakistani forces fired warning shots forcing the NATO helicopters to return to Afghanistan. Witnesses said that the helicopters had been flying at low altitude and crested panic among the people, who are worried over the U.S. drone strikes. Meanwhile, U.S. Embassy spokesperson Mark Stroh denied any NATO helicopter intruded inside Pakistan. He told the local media that ISAF and colleagues in Pakistan, who coordinate with them, have no record about the incursion into Pakistani airspace, hoping that it was just a matter of miscommunication.