Dec. 15 (UPI) -- Ukraine's Security Service said it has struck and disabled a Russian submarine using an underwater drone at the Black Sea port Novorossiysk, Russia.
The service said it completed a "unique special operation" against a Kilo-class submarine, damaging and disabling it for the first time. It said the attack used its "Sub Sea Baby" drones, which are the underwater version of the Sea Baby drones it uses against surface vessels and ports.
"As a result of the explosion, the submarine suffered critical damage and was effectively put out of action," CNN reported the SBU said.
The agency said the submarine is known as a "Black Hole" because of the hull's ability to absorb sound and stay undetectable by sonar. It said that class of submarine costs around $400 million to build, but international sanctions make it cost up to about $500 million.
Russian officials have not commented on the incident.
