Following the German armoured breakthrough at Sedan, the 2nd Panzer reached the mouth of the Somme River at Abbeville. After defeating French Army counterattacks near Cambrai, the Wehrmacht consolidated for an advance on the Channel ports. The Battle of Boulogne, Siege of Calais and Battle of Dunkirk were fought during the remainder of May. I. "Gruppe" fought actions in support of StG 76 over Dunkirk against RAF Fighter Command as it covered the evacuation; future fighter ace Emil Clade, who played a pivotal role in North Africa in 1942, claimed a 19 Squadron Supermarine Spitfire. Wilhelm Balthasar, commanding 1./JG 1 increased his total to 23 aerial victories and he became only the second fighter pilot to receive the Knight's Cross of the Iron Cross. The claim made by Clade was one of four made by I./JG 1 over Dunkirk, on 26 May, and the only claims made by the wing during the battle. Another pilot, Walter Adolph, 2./JG 1 began the war with the wing at this time, operating from Gymnich.