The KTB records that men (probably the look-outs from the bridge) were visible in the water but U-27 dived and withdrew, fearful that a second British submarine might be lurking nearby.

The same day, U-boat U-24 had sunk the White Star Liner SS Arabic, infuriating the crew of Baralong which were in the region but could do nothing.

For them this was no time to cease firing, even as the survivors of the crew appeared on the outer casing, struggling out of their clothes to swim away from her.

There was a mighty hiss of compressed air from her tanks and the U-27 vanished from sight in a vortex of giant rumbling bubbles, leaving a pall of smoke over the spot where she had been.

12 German survivors swam from the wreck U-27 to Baralong seeking safety, but commanding officer Godfrey Herbert, acting under unofficial advice relayed by two officers of the Admiralty's Secret Service branch to, "Take no prisoners from U-boats",[8] ordered his men, in violation of the Hague Conventions, to shoot the unarmed German survivors in the water with small arms, killing all 12.

Herbert then dispatched 12 Royal Marines from Baralong with orders to take no prisoners from the remaining German survivors aboard Nicosian.

The incident sparked outrage in Germany, and a debate took place in the Reichstag on 15 January 1916, where it was described as a "cowardly murder"; the German government soon announced that they would conduct reprisals, although they did not specify what they would be.