On 19 August , the morale of the Austro-Hungarians collapsed Destroying and thousands of soldiers retreated Escaping back into Austria-Hungary , many of them drowning Death in the Drina River as they fled Escaping in panic .

While there were 20,000 Chetnik insurgents located within the area of operations , they offered Giving no resistance to the German–NDH forces and many withdrew Escaping east across the Drina river to avoid Preventing_or_letting being engaged .

The aim Aiming of the operation was to target Aiming all insurgents between Sarajevo and the Drina river in eastern Bosnia .