The Prussian Navy dispatches a submarine battle group to the coast of Yamakami. They stay below 3 knots and run on silent, making them invisible to any sensor system. There are 15 Type-206 U Boats and 15 Type-551 U Boats. They are ordered to prevent the shipping of any military equipment out of the country. Any entering ships will be sunk after a single warning. Any leaving ships will also be sunk.

Any sueviving crew will be picked up by the U Boats and returned to the shore line.