Rundstedt's armies advanced rapidly into southern Poland, capturing Kraków on 6 September, but Reichenau's over-ambitious attempt to take Warsaw by storm on 9 September was repelled. Soon after, Blaskowitz's exposed northern flank was attacked by the Polish Poznań Army, leading to the major engagement of the Polish campaign, the Battle of the Bzura. Rundstedt and Manstein travelled to Blaskowitz's headquarters to take charge, and by 11 September the Poles had been contained in a pocket around Kutno. By 18 September the Poznan Army had been destroyed, and Warsaw was besieged. Reichenau's forces took Lublin on 11 September, while List's army was advancing to the east towards Lvov, where they eventually linked up with Soviet forces advancing from the east under the terms of the Molotov–Ribbentrop Pact. Warsaw surrendered on 28 September, and by 6 October fighting in southern Poland had ceased.