The Finns fielded the Erillinen Pataljoona 4 and about 150 men were trained before the beginning of summer 1941. At first, the units had as few as 15 men, but during the war this was increased to 60. On July 1, 1943, the units were organised in the 4th Detached Battalion. In 1944, a special unit with amphibious He 115 planes was founded to support the battalion. The total strength of the battalion was 678 men and 76 women (see Lotta Svärd).