Dover Castle Hospital Ship is sunk in the Mediterranean.

*She was torpedoed by the German U-boat UC-67 on 26 May 1917, while on passage from Malta to Gibraltar. The initial explosion killed seven boiler stokers but the crew was able to evacuate the wounded onto HMS “Chameleon”. The captain and a small crew tried to save the ship but she was hit by a second torpedo an hour later, and sank in three minutes.

The commander of UC-67 Karl Neumann was tried for the sinking of the hospital ship at Leipzig War Crimes Trials. However, he was found not guilty. Neumann admitted that he had torpedoed and sunk the British hospital ship but pleaded that he did so only in obedience to orders issued by the Admiralty. The German government had asserted that the enemy was using hospital ships for military purposes and declared on March 19, 1917 that German submarines would attack hospital ships not complying with several German conditions. The court held that Neumann believed the order to be a lawful reprisal and therefore was not personally responsible for the sinking. (http://en.wikipedia.org/wiki/HMHS_Dover_Castle)