In July 1943, the Germans launched Operation Citadel, in the region around Kursk, their last major offensive on the Eastern Front in the Second World War. It was the debut of the German Panther tank, although the numbers employed at the resulting Battle of Kursk were small and the brunt of the burden was carried by the Panzer III, StuG III, and Panzer IV. The campaign featured the largest tank battles in history. The high-water mark of the battle was the massive armour engagement at Prokhorovka, which began on 12 July, though the vast majority of armour losses on both sides were caused by artillery and mines, rather than tanks. Over 6,000 fully tracked armoured vehicles, 4,000 combat aircraft, and 2 million men are believed to have participated in these battles.