The new anti-aircraft communication links allowed areas threatened by German bombardment to be warned, German artillery spotting aircraft to be attacked and German artillery batteries to be fired on when they revealed themselves. From 1 to 7 June, the II Brigade RFC had from wireless interception, shot down one German aircraft, damaged seven and stopped artillery bombardments. Normal offensive patrols continued beyond the barrage line out to a line from Ypres to Roulers and Menin, where large formations of British and German aircraft clashed in long dogfights, once German air reinforcements began operating in the area. Longer-range bombing and reconnaissance flights concentrated on German-occupied airfields and railway stations and the night bombing specialists of 100 Squadron attacked trains around Lille, Courtrai, Roulers and Comines. Two squadrons were reserved for close air support on the battlefield and low attacks on German airfields.