Pakistan has thwarted an act of aggression by Afghan forces at Pak-Afghan border in Nushki-Ghaznali sector.According to security sources, Afghan forces opened fire on Pakistani posts. In retaliation, Pakistan forces targeted Afghan posts.The incident of exchange of fire took place on the Pak-Afghan border when Pakistani forces were repairing the fence.The security sources said that the Afghan forces suffered heavy losses due to effective retaliation by Pakistan. They said Pakistan will continue to take effective measures to protect its borders.The security sources said Pakistani security forces will not compromise their territorial integrity.Source: Radio Pakistan