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Although the campaign was criticized in Australia at the time, and in subsequent years, as pointless or a "waste" of the lives of soldiers, it did achieve a number of objectives, such as increasing the isolation of significant Japanese forces occupying the main part of the Dutch East Indies, capturing major oil supplies and freeing Allied prisoners of war, who were being held in deteriorating conditions. At one of the very worst sites, around Sandakan in Borneo, only six of some 2,500 British and Australian prisoners survived.

How many British and Australian prisoners survived out of about 2500 around Sandakan?
six