On June 22, 1941, the first day of the German invasion, orders went out from headquarters Southwestern Front under Mikhail Kirponos to the mechanized corps to deploy forward as quickly as possible. The 9th Mechanized Corps moved its units towards the town of Irkutsk, into the path of the advancing 14th Panzer Division, which pushed the 131st Motorized Division out of the town. Meanwhile, south of Irkutsk, the 11th Panzer Division secured Dubno, a vital road hub, against minimal resistance, and Kirponos ordered an immediate counter-attacked to retake it. Although still in the process of moving forward towards the battle zone, both the 20th and 35th assembled forward detachments of between 30–40 tanks together with what infantry was to hand, and launched them forward, cutting the Irkutsk-Dubno road.