The U-28 sea creature

A submarine commander said that when his submarine sank the steamer Iberian on 30 July 1915, an explosion threw a giant sea creature into the air.

On 30 July 1915 the submarine U 28, under Baron von Forstner, torpedoed the British steamer Iberian in the North Atlantic. The ship, about 600 feet long and carrying 5,223 tons, went down quickly with her bow pointing nearly straight up. About 25 seconds later a powerful explosion followed, which Wikipedia says was almost certainly her boilers. It threw wreckage some 80 feet above the sea.

Forstner reported that the blast also hurled a giant sea creature into the air. In one version it was about 60 feet long, with four limbs and big webbed feet, plus a tapering head and tail, and it stayed in sight for 10 to 15 seconds before going under. Another version gives the length as 20 metres and puts the event sixty nautical miles away, south of Fastnet Rock, at the corner of Ireland's southwest.

Skeptics point out that seven people died when the Iberian sank, which left roughly sixty-one survivors who spoke to English, Irish and American newspapers. None of their stories mention a creature.