Most of the Polish units that participated in the battle created the so-called First Assault Group (I Grupa Uderzeniowa), commanded by Piłsudski himself.

The Second Assault Group, under Wrzalinski, attacked from Warsaw and captured Mińsk Mazowiecki with the support of tanks.

Polish objective was to reach the road connecting Warsaw with Brzesc nad Bugiem to cut the supply lines and evacuation routes of Soviet Western Front.

Divided into two columns, the Poles advanced rapidly and crushed Soviet resistance with their tanks and artillery.

The 10th Rifle Division of the Red Army, which defended Debe Wielkie, abandoned its positions, and at about 6 p.m., two Polish armoured trains entered the rail station at Mińsk Mazowiecki, which forced the Soviets to retreat.