QUETTA Two helicopters of NATO forces violated Pakistani airspace on Tuesday in Chaman area, a bordering town of Balochistan with Afghanistan. Two helicopters violated Pakistani airspace for sometime and returned back after making flights on Killi Luqman, a village close to the Afghan border. The NATO helicopters entered into about 200 meters at 10:40 am inside Pakistani airspace and returned back to Spin Boldak area of Afghanistan to their airbase. The movement of NATO helicopters created panic among the local residents. Official sources in Chaman confirmed violation of Pakistani airspace by NATO helicopters and said that they could not say whether helicopters deliberately violated Pak airspace or by mistake. The sources said that the Nato helicopters come on zero point and returned back. Security was beefed up at Pak-Afghan border following the violation of Pak airspace.