The offensive commenced in the Baranow bridgehead at 04:35 on 12 January with an intense bombardment by the guns of the 1st Ukrainian Front against the positions of the 4th Panzer Army. Concentrated against the divisions of XLVIII Panzer Corps, which had been deployed across the face of the bridgehead, the bombardment effectively destroyed their capacity to respond; a battalion commander in the
68th Infantry Division stated that "I began the operation with an understrength battalion [...] after the smoke of the Soviet preparation cleared [...] I had only a platoon of combat effective soldiers left". The initial barrage was followed by probing attacks and a further heavy bombardment at 10:00. By the time the main armored exploitation force of the 3rd Guards and 4th Tank armies moved forward four hours later, the Fourth Panzer Army had already lost up to two-thirds of its artillery and one-fourth of its troops. The Soviet units made rapid progress, moving to cut off the defenders at
Kielce. The armored reserves of the 4th Panzer Army's central corps, the XXIV Panzer Corps, were committed but had suffered serious damage by the time they reached Kielce, and were already being outflanked. The XLVIII Panzer Corps, on the Fourth Panzer Army's southern flank, had by this time been completely destroyed, along with much of Recknagel's XLII Corps in the north. Recknagel himself would be killed by Polish partisans on 23 January. By 14 January, the 1st Ukrainian Front had forced crossings of the
Nida river, and began to exploit towards
Radomsko and the
Warthe. The 4th Panzer Army's last cohesive formation, the XXIV Panzer Corps, held on around Kielce until the night of 16 January, before its commander made the decision to withdraw. ,
Lower Silesian offensive, the
East Pomeranian offensive, and the battles in
Courland. The 1st Belorussian Front, to Konev's north, opened its attack on the German 9th Army from the Magnuszew and Puławy bridgeheads at 08:30, again commencing with a heavy bombardment. The 33rd and 69th armies broke out of the Puławy bridgehead to a depth of , while the 5th Shock and 8th Guards armies broke out of the Magnuszew bridgehead. The 2nd and 1st guards tank armies were committed after them to exploit the breach. The 69th Army's progress from the Puławy bridgehead was especially successful, with the defending LVI Panzer Corps disintegrating after its line of retreat was cut off. Though the 9th Army conducted many local counter-attacks, they were all brushed aside; the 69th Army ruptured the last lines of defence and took
Radom, while the 2nd Guards Tank Army moved on
Sochaczew and the 1st Guards Tank Army was ordered to seize bridgeheads over the
Pilica and attack towards
Łódź. In the meantime, the 47th Army had crossed the Vistula and moved towards Warsaw from the north, while the 61st and 1st Polish armies encircled the city from the south. The only major German response came on 15 January, when Hitler (against the advice of Guderian) ordered the
Panzerkorps Großdeutschland of
Dietrich von Saucken from
East Prussia to cover the breach made in the sector of the 4th Panzer Army, but the advance of Zhukov's forces forced it to detrain at Łódź without even reaching its objective. After covering the 9th Army's retreat, it was forced to withdraw southwest toward the Warthe.
Taking of Kraków; escape of the XXIV Panzer Corps On 17 January, Konev was given new objectives: to advance towards
Breslau using his mechanised forces, and to use the combined-arms forces of the 60th and 59th armies to open an attack on the southern flank towards the industrial heartland of Upper Silesia through
Kraków. Kraków was secured undamaged on 19 January after an encirclement by the 59th and 60th armies, in conjunction with the 4th Guards Tank Corps, forced the German defenders to withdraw hurriedly. The second stage of the 1st Ukrainian Front's objective was far more complex, as they were required to encircle and secure the entire industrial region of Upper Silesia, where they were faced by Schulz's 17th Army. Konev ordered that the 59th and 60th armies advance frontally, while the 21st Army encircled the area from the north. He then ordered Rybalko's 3rd Guards Tank Army, moving on Breslau, to swing southwards along the upper Oder from 20 January, cutting off 17th Army's withdrawal. In the meantime, the shattered remnants of the 4th Panzer Army were still attempting to reach German lines. By 18 January, Nehring and the XXIV Panzer Corps found that their intended route northwards had been blocked, so pulled back to the west, absorbing the remnants of XLII Corps that had escaped encirclement. Much of the remainder of XLII Corps was destroyed after being trapped around
Przysucha. Screened by heavy fog, the lead elements of XXIV Panzer Corps reached the Warthe on 22 January, and having linked up with Grossdeutschland Panzer Corps of von Saucken, were finally able to cross the Oder, some from their positions at the start of the Soviet offensive.
Withdrawal of 17th Army from Upper Silesia On 25 January, Schulz requested that he be allowed to withdraw his 100,000 troops from the developing salient around
Katowice/Kattowitz. This was refused, and he repeated the request on 26 January. Schoerner eventually permitted Schulz to pull his forces back on the night of 27 January, while Konev – who had allowed just enough room for the 17th Army to withdraw without putting up serious resistance – secured the area undamaged. On Konev's northern flank, the 4th Tank Army had spearheaded an advance to the Oder, where it secured a major bridgehead at
Steinau. Troops of the 5th Guards Army established a second bridgehead upstream at
Ohlau.
Advance of 1st Belorussian Front In the northern sector of the offensive, Zhukov's 1st Belorussian Front also made rapid progress, as the 9th Army was no longer able to offer coherent resistance. Its XXXVI Panzer Corps, which was positioned behind Warsaw, was pushed over the Vistula into the neighbouring
Second Army sector. Warsaw was taken on 17 January, as Army Group A's headquarters issued orders for the city to be abandoned; units of the 2nd Guards and 3rd Shock Armies entering the city were profoundly affected by the devastation wrought by German forces after the
Warsaw Uprising. Hitler, on the other hand, was furious at the abandonment of the "fortress", arresting Colonel
Bogislaw von Bonin, head of the Operations Branch of
OKH, and sacking both the 9th Army and XXXVI Panzer Corps commanders; generals
Smilo Freiherr von Lüttwitz and
Walter Fries. The 2nd Guards Tank Army pressed forward to the Oder, while to the south the 8th Guards Army reached Łódź by 18 January, and took it by 19 January. The 1st Guards Tank Army moved to encircle
Poznań by 25 January, and the 8th Guards Army began to fight its way into the city on the following day, though there was protracted and intense fighting in the
Siege of Poznań before the city would finally be taken. To the northeast of Zhukov's 1st Belorussian Front, the lead elements of Marshal
Rokossovsky's 2nd Belorussian Front taking part in the
East Prussian offensive had reached the Baltic coast of the
Vistula delta by 24 January and so succeeded in isolating
Army Group Centre in East Prussia. On 27 January, the abandoned
Wolf's Lair – Hitler's former headquarters on the Eastern Front, was captured.
Zhukov's advance to the Oder (
Bellinchen),
Pomerania, immediately east of the
Oder. It reads, in Russian, "March 1945, Death to the Germans." After encircling Poznań, the 1st Guards Tank Army advanced deep into the fortified region around the
Obra River against patchy resistance from a variety of
Volkssturm and
Wehrmacht units. There was heavier resistance, however, on the approaches to the fortress of
Küstrin. The German reorganisation of command structure that resulted in the creation of
Army Group Vistula was accompanied by the release of a few extra formations for the defense; the
V SS Mountain Corps, with two reserve infantry divisions, was deployed along the Obra and the prewar border fortifications known as the
Tierschtigel Riegel, while the
Panzergrenadier-Division Kurmark was ordered to reinforce it. On 16 January 1945,
Colonel Bogislaw von Bonin, the chief of the Operational Branch of the Army General Staff (
Generalstab des Heeres) gave Army Group A permission to retreat from Warsaw, overruling a direct order from Hitler for them to hold fast. Three days later von Bonin was arrested by the
Gestapo and imprisoned first at
Flossenbürg and then
Dachau concentration camp. The officer was eventually
liberated along with other prisoners in
South Tyrol by the US Army in May 1945. The military historian Earl Ziemke described the advance thus: On 25 January, Hitler renamed three army groups. Army Group North became
Army Group Courland; Army Group Centre became Army Group North and Army Group A became Army Group Centre. The 2nd Guards Tank and 5th Shock armies reached the Oder almost unopposed; a unit of the 5th Shock Army crossed the river ice and took the town of
Kienitz as early as 31 January.
Stavka declared the operation complete on 2 February. Zhukov had initially hoped to advance directly on Berlin, as the German defences had largely collapsed. However, the exposed northern flank of the 1st Belorussian Front in
Pomerania, along with a German counter-attack (
Operation Solstice) against its spearheads, convinced the Soviet command that it was essential to clear German forces from Pomerania in the
East Pomeranian offensive before the Berlin offensive could proceed. ==Liberation of Nazi concentration camps==