"Blau" finally opened as Army Group South began its attack into southern Russia on 28 June 1942. The German offensive started well. Soviet forces offered little resistance in the vast empty steppes and started streaming eastward. Several attempts to re-establish a defensive line failed when German units outflanked them. Two major pockets were formed and destroyed: the first, northeast of Kharkov, on 2 July, and a second, around Millerovo, Rostov Oblast, a week later. Meanwhile, the Hungarian 2nd Army and the German 4th Panzer Army had launched an assault on Voronezh, capturing the city on 5 July.