 The Group of General Krajowski made left wing of Polish 6th Army (General Jan Romer), attacked by Budyonny's cavalry.On July 13, 1920, 18th Infantry Division attacked Dubno, capturing the town, after heavy fighting with Soviet 11th Cavalry Division.General Krajowski, who was trying to get in touch with Polish 2nd Army, decided to send 36th Infantry Brigade to Chorupan.