in january 1943, axis forces launched case white, a combined strategic offensive aimed at destroying the yugoslav partisan resistance in the neighboring independent state of croatia. two corps of chetniks were sent from occupied serbia to support chetnik formations that had participated on the axis side in the offensive and had been defeated by the partisans following the latter's crossing of the neretva river. these corps were led by keserović and predrag raković and totaled 2,000 men. by early may 1943, mihailović became aware of the german intention to capture him and decided to return to german-occupied serbia. based on his orders, the two corps of chetniks led by keserović and predrag raković came from german-occupied serbia to the area of bijelo polje in the italian governorate of montenegro to escort him back to serbia.