Action of 16 March 1917 - Wikipedia

16th March 1917 Naval Action - 16th March 1917 In the Naval Action on the 16 March 1917 the German auxiliary cruiser Leopard was engaged and sunk by the British Armed boarding steamer HMS Dundee and the cruiser HMS Achilles.
Action.

SMS Leopard left port in March disguised as the Norwegian freighter Rena Norge on its mission to disrupt Allied shipping. On the 17 March it was stopped in the North Sea by the cruiser HMS Achilles and ordered to proceed to the boarding vessel HMS Dundee for inspection. Heavily outgunned Captain Hans von Laffert, the raider's commander, had no option but to proceed as directed. Captain Selwyn Day of the Dundee dispatched a launch containing a boarding party with an officer and five men to investigate the mysterious ship. Hans von Laffert realizing he was about to be discovered detained the party and after about an hour fired two torpedoes at the Dundee. The steamer got out of the way just in time and the torpedoes missed Captain Day's ship by twenty feet. Day ordered his guncrews to open fire and a hail of shells struck the Leopard damaging a gun and setting fires. The Achilles hearing the sound of gunfire returned to the scene and opened fire on the raider as the Dundee withdrew. Shortly after the Achilles's arrival the Leopard sank with all 319 hands. Damage to the British vessels was light and the only Allied casualties were the six boarding party members who were trapped in the Leopard when it sank. http://www.wartimememoriesproject.com/greatwar/shipscp/view.php?pid=4003