Visakhapatnam, Nov 07 (ANI): Search and rescue operations are underway as a naval vessel sank outside the Visakhapatnam harbour. One navy personnel was killed and four went missing, while 23 personnel were rescued safely after the Torpedo Recovery Vessel (TRV) A-72 sank on Thursday. The vessel had 28 navy personnel on board. Naval ships and aircrafts including P8I, Dorniers, and Seaking 42 C with night vision capabilities have been deployed for the search and rescue operation. TRV is an auxiliary vessel which is used to recover practice torpedoes fired by fleet ships and submarines.