around Kiev was located in the salient. By the end of July, the Soviet front lost some of its units due to the critical situation of the Southern Front (6th and 12th armies) caused by the German 17th army. While lacking mobility and armor, due to high losses in tanks at the Battle of Uman, on 3 August 1941, they nonetheless posed a significant threat to the German advance and were the largest single concentration of Soviet troops on the Eastern Front at that time. Both Soviet 6th and 12th armies were encircled at Uman, where some 102,000 Red Army soldiers and officers were taken prisoner. On 30 July 1941, the German forces resumed their advance onto Kiev, with the German 6th army attacking positions between the Soviet 26th army and the Kiev ukrep-raion troops. August On 7 August 1941, their advance was halted again by the Soviet 5th, 37th, and 26th armies, supported by the Pinsk Naval Flotilla. With the help of the local population around the city of Kiev, anti-tanks ditches were dug and other obstacles were installed, including the establishment of 750 pillboxes and 100,000 mines planted along the frontline segment. Some 35,000 soldiers were mobilized from local population along with some partisan detachments and two armored trains. On 19 July, Adolf Hitler had issued Directive No. 33, which cancelled the assault on Moscow in favor of driving south to complete the encirclement of Soviet forces surrounded in Kiev. On 12 August 1941, Supplement to Directive No. 34 was issued. This directive represented a compromise between Hitler, who was convinced the correct strategy was to clear the salient occupied by Soviet forces on right flank of Army Group Center, in the vicinity of Kiev, before resuming the drive to Moscow, and Franz Halder, Fedor von Bock and Heinz Guderian, who advocated an advance on Moscow, as soon as possible. The compromise required 2nd and 3rd Panzer Groups of Army Group Centre, which were redeploying in order to aid Army Group North and Army Group South respectively, be returned to Army Group Centre, together with the 4th Panzer Group of Army Group North, once their objectives were achieved. Then the three Panzer Groups, under the control of Army Group Center, would lead the advance on Moscow. Initially, Halder, chief of staff of the Oberkommando des Heeres (OKH), and Bock, commander of Army Group Center, were satisfied by the