Soldiers of the Estonian Waffen Grenadier Division had only light arms and antitank weapons in the form of German panzerfausts.

The 8th Rifle Corps surrounded about 1,500 Estonians retreating from the Tannenberg line in the Sinimäed Hills.

Several groups of Estonians led by Obersturmführer Hando Ruus managed to break out the Soviet encirclement and escape towards west.

However, on September 22, the largest group was taken by surprise in a forest near Ambla and most of the men were taken prisoner or killed.

The Soviet Rifle Corps lost 73 men killed, of whom 57 had Estonian names.