 On 3 November , the British began a bombardment in an attempt to destroy or neutralize Königsberg and Somali . Königsberg was protected by the thick mangrove swamps , which concealed the ship and offered a degree of cover from British shellfire , especially while the British ships remained outside the river . A collier , Newbridge , was converted into a blockship to be sunk in the main channel of the delta to prevent Königsberg 's escape . Despite heavy German fire from both sides of the river , the British successfully sank Newbridge across one of the delta mouths on 10 November , though the German raider could still put to sea via other channels . Looff decided to move his ship further upriver , to make it more difficult for the British to destroy her . In doing so , his ship would occupy a disproportionate number of British vessels that could otherwise have been employed elsewhere . In the course of the campaign , the British reinforced the squadron blockading the Rufiji with additional cruisers , including Pyramus and the Australian HMAS Pioneer . 
