This was a German and Croat operation by Generalleutnant Hans Mickl’s 392nd Division (kroatisch) against the 13th ‘Primorsko-goranska’ Assault Division of Marshal Josip Broz Tito’s partisan forces in the Mrkopalj region which it held since the capitulation of Italy in September 1943 (30 June/1 July 1944).
The 3/846th Grenadierregiment was moved from Otočac to the area to the south-east of Josipdol to free the 33rd Ustaše Battalion for the operation, which began on 30 June with the attackers divided into three groups, in the form of the 2/847th Grenadierregiment and parts of the Kampfgruppe ‘Rijeka’ advancing toward Lokve-Delnice, the 392nd Aufklärungsabteilung and 2/846th Grenadierregiment advancing from Drežnica using narrow mountain roads toward Mrkopalj, and the 33rd Ustaše Battalion with two pieces of artillery of the 1/392nd Artillerierregiment and one company of the 3/846th Grenadierregiment advancing toward Vrbovsko.
By the evening of the first day the second group had covered 26 miles (42 km) of difficult mountain road to reach Mrkopalj and surprise the partisan town command, forcing it to flee. The other groups encountered only light resistance from the 1st and 2nd Detachments as most of 13th Division was committed to an attack on Bosiljevo together with the 15th ‘Slovenia’ Division in order to relive pressure on Žumberak, where another anti-partisan operation was under way.
After destroying several partisan warehouses and barracks, the German group left Mrkopalj and advanced to the east to aid the garrison in Bosiljevo. The Germans and Croats could not undertake the permanent garrisoning of the area, and after the destruction of partisans’ local infrastructure left the Mrkopalj area.