The climax of the Battle of Tannenberg Line was the Soviet attack on July 29. The Soviet shock units suppressed the German resistance at the Lastekodumägi, while the Soviet main forces suffered heavy casualties in the subsequent assault at the Grenaderimägi. The Soviet tanks encircled the Grenaderimägi and the westernmost Tornimägi. At the same time, SS-Obergruppenführer Felix Steiner sent out the remaining seven German tanks which hit the surprised Soviet armoured forces back. This enabled the multi-national combat unit to re-conquer the Grenaderimägi into German hands. Of the 136,830 Soviets initiating the Narva Operation, July 1944, a few thousand had survived and the Soviet tank regiments were demolished.