 Once Detzner reached the vicinity of the Sattelberg Mission , nearby villagers in the Borrum valley housed him and his remaining men , which had dwindled to about 20 soldiers , plus four European officers and , on his behalf , the villagers sought assistance from the Sattelberg director , Christian Keyser , and another missionary , Otto Thiele . They reluctantly agreed to keep Detzner 's presence a secret . Among the villagers , Detzner established a base camp from which he could depart at short notice . The valley was relatively secure for him , and inaccessible for the Australians , but if they ventured too close to his base , Detzner and his men would retreat into the mountainous Saruwaged , or , if necessary , further into the Finisterre mountains . These were rugged and remote locations , accessible to Detzner , who had the help of native guides , but which the Australians , who usually traveled in larger patrols , could not penetrate . 
