A 13 November 1995, car bombing in Riyadh led the U.S. forces stationed at Khobar Towers to raise the threat condition to THREATCON DELTA. Days after the attack, military commanders briefed soldiers and airmen at Khobar that the U.S. had received anonymous communications from an organization claiming to have carried out the Riyadh attack. The attackers claimed their goal was to get the United States Armed Forces to leave the country, and that Khobar Towers would be attacked next if troop withdrawal did not begin immediately. It was at this time that surveillance and other suspicious activity near the perimeter fences of Khobar Towers was noted by United States Air Force Security Forces; however, the forces were forbidden by the Saudi government to act in any capacity outside the perimeter of the compound, and the surveillance continued with near impunity.