sentences:  On 22 June 1941 when the German Operation Barbarossa began, it was serving with the 51st Rifle Corps of the 22nd Army.By 29 June 1941, after the effective destruction of the 37th Rifle Division, a composite regiment (20th Rifle Regiment) formed mostly from 37th Rifle Division rear units ("Tyl") was attached to the division.The 153rd Rifle Division was one of the first divisions to be designated a Guards formation, becoming 3rd Guards Rifle Division on September 18, 1941, due to 'its combat record in Belarus and Smolensk'.