 The bridgeheads at Serock, the confluence of the Bug and Narew Rivers, had been established by the Soviet 65th Army at the end of the Lublin–Brest Offensive.The German XX Corps of Second Army was deployed in defence.On 3 October elements of the 3rd and 25th Panzer Divisions, supported by the 252nd Infantry Division, were thrown into an attack to eliminate the 65th Army's positions in the bridgehead.