To the south the French retook Mulhouse on 19 August and then withdrew. On 24 August at the Battle of the Mortagne a limited German offensive in the Vosges, the Germans managed a small advance, before a French counter-attack retook the ground. By 20 August a German counter-offensive in Lorraine had begun and the German 4th and 5th Armies advanced through the Ardennes on 19 August towards Neufchâteau. An offensive by French Third and Fourth armies through the Ardennes began on 20 August, in support of the French invasion of Lorraine. The opposing armies met in thick fog and the French mistook the German troops for screening forces. On 22 August the Battle of the Ardennes began with French attacks, which were costly to both sides and forced the French into a disorderly retreat late on 23 August. The Third Army recoiled towards Verdun, pursued by the 5th Army and the Fourth Army retreated to Sedan and Stenay. Mulhouse was recaptured again by German forces and the Battle of the Meuse caused a temporary halt of the German advance.