The French deployed five armies on the frontier. The French Plan XVII was intended to bring about the capture of Alsace-Lorraine. On 7 August, the VII Corps attacked Alsace to capture Mulhouse and Colmar. The main offensive was launched on 14 August with the First and Second Armies attacking toward Sarrebourg-Morhange in Lorraine. In keeping with the Schlieffen Plan, the Germans withdrew slowly while inflicting severe losses upon the French. The French Third and Fourth Armies advanced toward the Saar River and attempted to capture Saarburg, attacking Briey and Neufchateau but were repulsed. The French VII Corps captured Mulhouse after a brief engagement on 7 August but German reserve forces engaged them in the Battle of Mulhouse and forced a French retreat.