While most Herero escaped the battle, their retreat led to the near extinction of their people in an act of genocide. Many of the refugee Hereros died of thirst and exhaustion during their trek through the desert. German patrols later found skeletons around holes 8–16 m (25–50 ft) deep dug in a vain attempt to find water. Tens of thousands of the Herero died of thirst, starvation, or disease. Those who attempted surrender were summarily shot. After Trotha's extermination order was countermanded by Berlin, captured survivors were sent to a concentration camp at Shark Island.