 Complete the following phrase:  After the surrender of Belgium on 28 May 1940, two Brunos were used by Battery 655 between 8 and 10 June to fire on Brimont and Reims from Amifontaine. One gun was destroyed when a shell detonated prematurely in the barrel while firing on those targets. By the end of 1941, two Brunos were assigned to Battery 721 and stationed at Le Verdon-sur-Mer defending the mouth of the Gironde Estuary under the command of Artillery Group Gironde-South . The battery was able to retreat to Germany by 1 September 1944 after the 