to the Partisan side. In 1943, the Allies officially recognized the Partisans as an Allied fighting force. Winston Churchill highlighted the strength and importance of the Partisans and advised the Yugoslav government to reach an agreement with Tito, whose forces generated an appeal among all ethnic groups. End of the war The arrival of Soviet ground troops in the Belgrade Offensive and Allied logistical support enabled the Partisans to increase their offensive actions. By the end of 1944, with the help of the Red Army, they established control in Serbia, North Macedonia, Montenegro and Dalmatia. German forces retreated from Serbia, together with Nedić's forces. The Wehrmacht and the HOS established a front in Syrmia to secure the retreat of the German Army Group E from the Balkans. The Partisans conducted mass killings of POWs and ethnic Germans after securing control of Serbia. The Communist leadership adopted a political decision on the expulsion of the German national minority, whom they held collectively responsible for Nazi crimes, and the confiscation of their property. Germany attempted to evacuate the entire German population from Yugoslavia to the Reich, but in late 1944 there were still around 150,000 Germans in Partisan-controlled Vojvodina. By May 1945, most were interned in over 40 concentration camps in the region, in which around 46,000 died. In May 1944, Tito founded an intelligence service known as the Department for People's Protection (OZNA), modeled after the Soviet NKVD. It represented a military intelligence service and a political secret police of the Communist Party. In August 1944, he founded an army unit called the People's Defence Corps of Yugoslavia (Korpus narodne odbrane Jugoslavije, KNOJ), whose explicit assignment was to "liquidate Chetnik, Ustaša, White Guard and other anti-people gangs". With the growth of the Partisans, who provided Croats an alternative that appeared more in Croatia's national interest, and the general dissatisfaction with the Ustaše and Nazi German authorities, the NDH had serious difficulties in mobilizing new troops. When in August 1944, a coup d'état against Ante Pavelić, known as the Lorković–Vokić plot, failed, its conspirators were arrested or executed. The main plotters wanted to align NDH with the Allies. The outcome of the plot caused further demoralization. As the war progressed, the desertion rate in the NDH armed force increased, especially among the Croatian Home Guard, the regular army. On 30 August 1944, Tito offered amnesty to Croatian Home Guards, Slovene Home Guards,