 Commander Bey was ordered during the afternoon of 10 April to return to Germany with all seaworthy ships that evening , but Koellner needed more time to refuel and make repairs . They were completed the following day and the ship was ordered to patrol the mouth of the Ofotfjord that evening for picket duty . She ran aground shortly before midnight and started to take on water through damaged hull plating . She returned to Narvik on the morning of 12 April . Koellner could not be repaired with the resources available to the Germans so she was ordered to Tårstad , inside the Ramnes Narrows at the mouth of the Ofotfjord , to act as a floating battery in case of British attack . The water at Tårstad was too shallow to use torpedoes , so they were off @-@ loaded and transferred to her sisters Bernd von Arnim and Theodor Riedel . Much of her fuel was also transferred to them and 90 men not needed were put ashore . 
