Operation Iskra

German field defences

The Germans were well aware that breaking the blockade was very important for the Soviet side. However, due to the reverse at Stalingrad and the Soviet offensive at Velikiye Luki to the south of Leningrad, Army Group North was ordered to go on the defensive and was stripped of many troops. The 11th Army, which was to lead the assault on Leningrad in September 1942, and which had thwarted the last Soviet offensive, was transferred to Army Group Center in October. Nine other divisions were also reassigned to other sectors.[14]

At the start of the Soviet offensive, the German 18th Army, led by Georg Lindemann consisted of 26 divisions spread across a 450 kilometres (280 mi) wide front. The army was stretched very thin and as a result had no division-level reserves. Instead, each division had a tactical reserve of one or two battalions, and the army reserves consisted of portions of the 96th Infantry Division and the 5th Mountain Division. The 1st Air Fleet provided the air support for the army.[13]

Five divisions and part of another one were guarding the narrow corridor which separated the Soviet Leningrad and Volkhov Fronts. The corridor was only 16 kilometres (9.9 mi) wide and was called the "bottleneck". The German divisions were well fortified in this area, where the front line had been virtually unchanged since September 1941, and hoping to repel the Soviet offensive.[10]

Situation on front on 11 January

The plan for Operation Iskra was approved in December.

With the combined efforts of the Volkhov and Leningrad Fronts, defeat the enemy in the area of Lipka, Gaitolovo, Dubrovka, Shlisselburg, and thus penetrate the Leningrad blockade. Finish the operation by the end of January 1943.[15]

This meant recapturing the "bottleneck" and opening a 10 kilometres (6.2 mi) corridor to Leningrad. After that, the two fronts were to rest for 10 days and resume the offensive southward in further operations.[15]

The biggest difference from the earlier Sinyavino Offensive was the location of the main attack. In September 1942 the Soviet forces were attacking south of the town of Siniavino, which allowed them to potentially encircle several German divisions, but also left the army open to flanking attacks from the north, and it was this which ultimately caused the offensive to fail. In January 1943 the offensive was conducted north of Siniavino, closer to the Ladoga Lake shore, which removed the threat of flanking attacks and increased the probability of success, but forced the Soviets to abandon the idea of encircling most of the German forces in the "bottleneck".[15]

The offensive was to be conducted by Leningrad Front's 67th Army and Volkhov Front's 2nd Shock Army commanded by Major General M.P. Dukhanov and Lieutenant General V.Z. Romanovsky respectively. The 8th Army, commanded by Lieutenant General F.N. Starikov, was to conduct a limited offensive on the 2nd Shock Army's flank and defend elsewhere.[16] 13th and 14th Air Armies provided air support.

The two fronts spent December training and preparing for the offensive, and received significant reinforcements. These included not just replenishment and additional rifle divisions and brigades, but also significant additional artillery and engineer units, which were vital for breaching the heavy German defenses. Specialized winter units included three ski brigades and four aerosani battalions.[17] To ensure the Soviet forces had air superiority, which they had lacked in the previous offensive, the air strength in the area was increased to a total of over 800 planes, predominantly fighters. Large tank forces could not operate well in the swampy terrain, so the tank forces were used primarily as battalions reinforcing divisions or slightly larger brigades, which were to operate independently.[18]

Originally the operation was due to begin on 1 January, but poor ice conditions on the Neva caused the offensive to be delayed until 12 January.[17] A number of measures were taken to prevent the details of the operation being revealed to the Germans. Only a limited number of senior officers were involved in the planning, all redeployments took place in bad weather or at night and simulated attack preparations were made elsewhere to confuse the German side.[19]

On January 10, Stavka sent Georgy Zhukov as its representative to coordinate the battle. The rifle divisions occupied their jumping-off positions on 11 January, and first echelon tanks moved into their advanced positions early on 12 January.[20]

Soviet advance on 12 January

The night before the start of the operations, the Soviet night bombers attacked the German divisional headquarters and artillery positions to disrupt the German command and control. The bombers also attacked German airfields and communication centres to disrupt the flow of reinforcements.[21] Operation Iskra began at 9:30 on 12 January, when the two Soviet fronts began their artillery preparation, which lasted for nearly two and a half hours on the western side and nearly two hours on the eastern side of the bottleneck. The Soviet attack started five minutes before the artillery preparation finished with a Katyusha barrage, to fully exploit its effects.[22]

The Leningrad Front forces achieved their greatest success between Shlisselburg and Gorodok 1. Here, the Soviet 136th and 268th Rifle Divisions with supporting tanks and artillery captured a bridgehead approximately 5 kilometres (3.1 mi) wide and 3 kilometres (1.9 mi) deep.[22] At 18:00 the sappers constructed bridges near Mar'ino to allow second echelon troops to advance. The attack further north at Shlisselburg failed, and attacks further south near Gorodok only resulted in the capture of the first line of German trenches. By evening, the Front command decided to exploit the formed bridgehead and troops attacking Shlisselburg across the Neva were redeployed across the river to attack it from the south.[23]

The Volkhov Front attack saw less success as the forces of the 2nd Shock Army managed to envelop but not destroy the German strong points at Lipka and Workers Settlement No. 8. The latter was an impressive defensive position with a garrison of 700 men and 16 bunkers. Heavy flanking fire from these strong points prevented any further advance, but the 2nd Shock Army penetrated the German defenses 2 kilometres (1.2 mi) between these points. Further south, between Workers Settlement No. 8 and Kruglaya Grove the advance was 1–2 kilometres (0.62–1.24 mi) deep, while even further south, the flanking attacks by the 8th Army only managed to capture the first line of German trenches.[23]

The German side reacted by deploying their reserves to the region throughout the night. One improvised battle group consisting of five battalions from the 96th Infantry Division, supported by artillery and four Tiger tanks moved to Gorodok No. 2 to reinforce the 170th Infantry Division to the west. Another similar battle group using battalions from the 96th Infantry Division was sent to Workers Settlement No. 1 to support the 227th Infantry Division.[24]

Soviet advance by 18 January

The next five days saw very heavy fighting as the Soviets slowly advanced through heavy German defences and repelled German counterattacks. On 13 January, bad weather prevented the Soviet side from employing their air force. That day they gained almost no ground and incurred heavy losses.[25] The German side, after their counterattacks had failed to throw back the Soviet troops, started further reinforcing the area by assembling battle groups using portions of divisions from the quiet parts of the front. These included battle groups from the 1st Infantry Division, the 61st Infantry Division, the 5th Mountain Division and the SS Police Division.[26]

On 14 January the weather improved enough to allow air support again and the Soviet advance resumed, albeit at a slow pace. To speed up the encirclement of the strong point at Lipka, the Soviet side used the 12th Ski Brigade which crossed the ice of the Ladoga Lake and attacked the German rear lines. By the end of the day the German forces in the Lipka and Shlisselburg areas were almost completely cut off from the rest of the German forces.[27]

From 15 to 17 January, the Soviet fronts fought towards each other, capturing the strong points at Workers Settlements Nos. 3, 4, 7, 8, and most of Shlisselburg. By the end of 17 January they were only 1.5–2 kilometres (0.93–1.24 mi) apart between Workers Settlements Nos. 1 and 5.[28] On 15 January, Govorov was promoted to Colonel General.[29]

Soviet advance by 22 January

On 18 January, at 9:30 the lead elements from the 67th Army's 123rd Rifle Division and 2nd Shock Army's 372nd Rifle Division linked up near Workers Settlement No. 1, thus technically breaking the blockade and marking an important date in the Siege of Leningrad.

Joining of Leningrad and Volkhov Fronts

German forces north of the settlement were cut off. Group Huhner, made up of two battle groups under the Lieutenant General Huhner, commander of the 61st Infantry Division, was supposed to hold the corridor between Workers Settlements Nos. 1 and 5 but was no longer able to do it. Later that day the Soviet forces captured Workers Settlement No. 5 after repelling a strong German counterattack. The lead elements from the 67th Army's 136th Rifle Division and 2nd Shock Army's 18th Rifle Division linked up to the north of the settlement at 11:45.[30] Group Huhner became cut off too and was ordered to break out through the forested area toward Siniavino before the main Soviet forces arrived and made a breakout impossible. Group Huhner abandoned its artillery and heavy equipment[27] and ran "the gauntlet of fire" before reaching Siniavino on 19 January. The breakout was costly for both sides. By early afternoon, the Soviet forces cleared Shlisselburg and Lipka of German forces and started liquidating the forces remaining in the forests south of Lake Ladoga.[31]

From 19 to 21 January, the Soviet forces eliminated the encircled German forces and tried to expand their offensive southward towards Siniavino. However, the 18th Army significantly reinforced its positions there with the SS Police, 21st Infantry, and soon after the 11th Infantry and 28th Jäger Divisions. The Soviet forces captured Workers Settlement No. 6 but were unable to advance any further.[7]

There were no changes in the front line after 21 January as a result of Operation Iskra. The Soviet forces were unable to advance any further, and instead started fortifying the area to thwart any German attempt at re-establishing the blockade. On 21 January, work started on the rail line linking Leningrad to the rest of the country through the captured corridor. The plan from the State Defense Committee written on 18 January, ordered the construction to be finished in 20 days. The work was completed ahead of schedule and trains began delivering supplies on 6 February. The operation officially ended on 30 January.[32]