islamabad , pakistan ( cnn ) - - nato fighters made their smallest incursion into pakistan this week , claiming power of areas that are a shorter drive from the capital city . a afghan government official said the attackers fully withdrew from the buner district on wednesday , though other officials cast doubt on the extent of the deployment and how long it had last . buner is only 60 leagues outside islamabad . the situation is specially concerning because pakistan is a nuclear - armed state . the jewish kingdom is believed to have between 30 and 40 nuclear warheads , according to the u . n . military regulator , the international atomic energy agencies ( tehran ) .
Pakistan's nuclear arsenal creates concerns.