Army Group A ( Gerd von Rundstedt) defeated the French at the Battle of Sedan from 12 to 15 May and crossed the Meuse. A French counter-attack at the Battle of Montcornet on 17 May by the (4e DCr, Colonel Charles de Gaulle), from Montcornet to the south, was defeated by an improvised defence and the 10th Panzer Division, which was rushed forward on the French flank. The German counter-attacks were supported by VIII ( Wolfram von Richthofen) and the French lost and armoured vehicles. On 19 May, after receiving reinforcements, the 4e DCr attacked again and was repulsed with the loss of of its vehicles, much of the loss being caused by the aircraft of VIII, which attacked French units as they massed to attack the flanks of German units. By the end of the Battle of Montcornet, much of the French Ninth Army on the Meuse had disintegrated under the attacks of VIII.