At the outbreak of the German invasion of the Soviet Union on 22 June 1941, NKVD and NKGB hastily organized evacuation of numerous political prisoners into the interior of the Soviet Union. In many instances, instead of evacuating, NKVD carried out mass executions. Some of the evacuated prisoners, including about a hundred Lithuanians from Kaunas Prison, were gathered at the Pishchalauski Castle in Minsk which already housed a number of Polish prisoners, members of the Union of Armed Struggle. On 24 June, 15 Lithuanians who had received death sentences before the evacuation were executed (among them was , Lithuanian Minister of the Interior in 1929–1934). On 25 June, about 2,000 prisoners were marched on foot by troops from the 42nd NKVD brigade to Chervyen. Along the way, about 500 prisoners were executed for failing to keep up. A Soviet report claimed that 209 prisoners were shot due to confusion and a German air attack. On 26 June, the remaining prisoners were placed in the Chervyen prison. A few criminal prisoners were released when they volunteered for the Red Army.