The 'Battle of Porkuni' was the largest engagement between Estonians serving in the Soviet army and Estonian pro-independence and Waffen-SS units between Lake Porkuni and the village of Sauvälja about 4.35 miles (7 km) to the north-east of the town of Tamsalu during the Leningrad Front’s 'Tallinn Offensive Operation' (21 September 1944).

The 249^th Regiment of General Leytenant Lembit Pärn’s VIII Estonian Corps was well equipped with heavy machine guns and mortars, and was supported by artillery and armour, while the men of SS-Brigadeführer Franz Augsberger’s 20^th Waffen-Grenadierdivision der SS (estnische Nr. 1) of SS-Obergruppenführer und General der Waffen-SS Felix Steiner’s III SS Panzerkorps in Generalleutnant Johannes Friessner’s Armeeabteilung 'Narwa' within Generaloberst Ferdinand Schörner’s Heeresgruppe 'Nord' had only light weapons and a number of Panzerfaust anti-tank rockets.

The VIII Corps surrounded about 1,500 Estonians retreating from the 'Tannenberg-Linie' in the Sinimäed hills under the command of Juhan Vermet, and in the ensuing battle more than 500 of the surrounded Estonians were killed and about 700 taken prisoner.

Several groups of Estonians led by SS-Obersturmführer Hando Ruus managed to break out of the Soviet encirclement and escape to the west. However, on 22 September the largest of these group was taken by surprise in a forest near Ambla and most of the men were killed or taken prisoner.

Villagers buried 273 dead Estonians in German uniform. The VIII Corps lost 73 men killed, of whom 57 had Estonian names.