Can confirm.
I've seen 2 subs on the Indian Ocean, pretty darn close. I Brit, 1 American I believe. Not on Rader, no transponders. . I was on watch, as we look out for objects in the sea at night that might scupper the boat
Oops
http://nymag.com/intelligencer/2018/04/fired-white-house-official-joins-doj-at-trumps-insistence.html?gtm=bottom