The first British air raids on Berlin took place in the night of 25 August 1940. They were followed by infrequent attacks during the ensuing months. This first phase of the air war lasted until the fall of 1941. Thereafter, virtually no air raids were flown against Berlin until January 1943. In all of 1942, Berlin’s air raid sirens sounded only nine times. Even though Berlin was not the only goal of the strategic air war, it was still a very important one, being not only the capital of the German Reich, but also an important industrial and armaments centre. Starting in March 1944, the Royal Air Force (RAF) night time raids were supplemented by daytime attacks on Berlin by the U.S. Army Air Forces (USAAF). In February and March 1945, the capital was attacked from the air almost daily. This American and British bombing offensive was designed to be a visible contribution to the Soviet ground offensive which had been launched on 12 January 1945 from the Vistula river in Poland. The American air attack on Berlin of 3 February 1945 was one of the heaviest of the entire war. On that day, Berlin suffered 2.500 dead from the air raid, and 100.000 people saw their homes destroyed. The bombing on 3 February 1945 focused on the government district and was designed to break the will of the Berlin people. However, that strategy failed. Rather, support for the Nazi regime increased. The RAF and USAAF stopped their air attacks on 16 April 1945. The Soviet Union continued the air war to support the ground offensive in Berlin.