The Second Battle of Kharkov or Operation Fredericus was an Axis counter-offensive in the region around Kharkov (Kharkiv, Ukraine) against the Red Army Izium bridgehead offensive conducted 12–28 May 1942, on the Eastern Front during World War II. Its objective was to eliminate the Izium bridgehead over Seversky Donets or the "Barvenkovo bulge" () which was one of the Soviet offensive's staging areas. After a winter counter-offensive that drove German troops away from Moscow but depleted the Red Army's reserves, the Kharkov offensive was a new Soviet attempt to expand upon their strategic initiative, although it failed to secure a significant element of surprise. On 12 May 1942, Soviet forces under the command of Marshal Semyon Timoshenko launched an offensive against the German 6th Army from a salient established during the winter counter-offensive. After a promising start, the offensive was stopped on 15 May by massive airstrikes. Critical Soviet errors by several staff officers and by Joseph Stalin, who failed to accurately estimate the 6th Army's potential and overestimated their own newly raised forces, facilitated a German pincer attack on 17 May which cut off three Soviet field armies from the rest of the front by 22 May. Hemmed into a narrow area, the 250,000-strong Soviet force inside the pocket was exterminated from all sides by German armored, artillery and machine gun firepower as well as 7,700 tonnes of air-dropped bombs. After six days of encirclement, Soviet resistance ended, with the remaining troops being killed or surrendering. The battle was an overwhelming German victory, with 280,000 Soviet casualties compared to just 20,000 for the Germans and their allies. The German Army Group South pressed its advantage, encircling the Soviet 28th Army on 13 June in Operation Wilhelm and pushing back the 38th and 9th Armies on 22 June in Operation Fridericus II as preliminary operations to Case Blue, which was launched on 28 June as the main German offensive on the Eastern Front in 1942. Background General situation on the Eastern Front By late February 1942, the Soviet winter counter-offensive, had pushed German forces from Moscow on a broad front and then ended in mutual exhaustion. Stalin was convinced that the Germans were finished and would collapse by the spring or summer 1942, as he said in his speech of 7 November 1941. Stalin decided to exploit this perceived weakness on the Eastern Front by launching a new offensive in