 Meanwhile, the Hungarian 2nd Army and the German 4th Panzer Army had launched an assault on Voronezh, capturing the city on 5 July.The initial advance of the 6th Army was so successful that Hitler intervened and ordered the 4th Panzer Army to join Army Group South (A) to the south.A massive traffic jam resulted when the 4th Panzer and the 1st Panzer both required the few roads in the area.