[Fish In The Water]

Originally Posted by jimbuna

The first and only time during WWII that a sub was destroyed by another sub whilst both were submerged.

http://uboat.net/boats/u864.htm

Makes it all the more remarkable...

BTW, just read the following on the linked page:

This is the only known incident in all of naval warfare in which one submarine sinks another while both are submerged.

Just wondering if it's WWII or 'all of naval warfare?'