From May 14 to June 8, 1920, the army fought in the Western Front counterattack against the Polish Kiev Offensive, the May Offensive. In the counterattack, planned by front commander Mikhail Tukhachevsky, the 16th Army was to frontally attack the Polish 4th Army at Borisov and Igumen and keep it from moving to reinforce threatened Polish units, while the 15th Army, the main force, would advance southwest towards Molodechno, then wheel around and push the 1st Polish Army into the rear of the 4th, driving them into the Pripet marshes and destroying them there. The attack began on May 14, but failed when the Soviet advance was unable to build momentum and the 15th Army was counterattacked and forced into a disorderly retreat at the beginning of June. The 16th Army crossed the Berezina and created a bridgehead, but was itself counterattacked and forced to retreat back across the Berezina.