During World War II Fritz Klingenberg, leading a reconnitoring patrol into Belgrade, sneaked into the city through enemy lines with just 6 men. The Yugoslav Army had thousands of men stationed in the capital, having retreated to the city from the countryside in order to make a defence against the invading German army. After a number of firefights with Yugoslav troops, Klingenberg made his way to the centre of the city. Using captured trucks, and parading captured Yugoslav troops, he presented himself to the Mayor, pretending to be a larger force. The Mayor surrendered to his forces, at which point Klingenberg gathered a number of German flags from the embassy and ran them up various flagpoles in the city. The Yugoslav troops gave up, believing that there had been a general surrender. Shortly, another smaller force of 15 Germans came into the city, and started also pretending to be a larger group, by driving captured vehicles repeatedly around the city so as to appear to be greater in number. Some time later, the actual German Army arrived at the outskirts of the city, expecting to have to fight their way into the city (which had a substantial troop presence), they for a while refused to believe the city had been captured by Klingenberg. Belgrade was then fully occupied by the German Army later the same month and Belgrade became the seat of the puppet Nedić regime, headed by General Milan Nedić. Klingenberg was awarded the Knight's Cross of the Iron Cross for the capture of the city.