Unlike the Americans, the British did not assign specific units to border duty but rotated the task between the divisions of the British Army of the Rhine. The border was also patrolled in the British sector by the British Frontier Service, the smallest of the Western border surveillance organisations. Its personnel served as a liaison between British military and political interests and the German agencies on the border. The BFS was disbanded in 1991 following Germany's reunification. The United States Army maintained a substantial and continuous military presence at the inner German border throughout the entire period from 1945 to after the end of the Cold War. Regular American soldiers manned the border from the end of the war until they were replaced in 1946 by the United States Constabulary, which was disbanded in 1952 after policing duties were transferred to the German authorities. It was replaced by two dedicated armoured cavalry regiments assigned to provide a permanent defence. The 2nd Armored Cavalry Regiment based at Nuremberg and the 14th Armored Cavalry Regiment based at Fulda – later replaced by the 11th Armored Cavalry Regiment – monitored the border using observation posts, ground and air patrols, countering intrusions and gathering intelligence on Warsaw Pact activities. Cross-border contacts There was little informal contact between the two sides; East German guards were under orders not to speak to Westerners. After the initiation of détente between East and West Germany in the 1970s, the two sides established procedures for maintaining formal contacts through fourteen direct telephone connections or Grenzinformationspunkte (GIP, "border information points"). They were used to resolve local problems affecting the border, such as floods, forest fires or stray animals. For many years, the two sides waged a propaganda battle across the border using propaganda signs and canisters of leaflets fired or dropped into each other's territory. West German leaflets sought to undermine the willingness of East German guards to shoot at refugees attempting to cross the border, while East German leaflets promoted the GDR's view of West Germany as a militaristic regime intent on restoring Germany's 1937 borders. During the 1950s, West Germany sent millions of propaganda leaflets into East Germany each year. In 1968 alone, over 4,000 projectiles containing some 450,000 leaflets were fired from East Germany into the West. Another 600 waterproof East German leaflet containers were recovered from cross-border rivers. The "leaflet war" was eventually ended by mutual