(Image: GETTY - Twitter/ @capt_navy )

The Kilo-class submarine, dubbed the "Black Hole" due to its ability to disappear suddenly, has been snapped leaving the major Black Sea port of Sevastopol.

The vessel is a diesel-electric attack submarine made in Russia, specially designed for missions in shallow waters.

The photo was taken by Twitter user "Capt" then spotted by US Submarine Veteran and expert, Eric Moreno who believes it could be heading to the Kerch Strait – which separates the Black Sea and the Sea of Azov where Russia captured Ukrainian sailors.

But Mr Moreno believes there could also NATO vessels could also be engaging in a precarious game of cat and mouse around the area and the Black Sea.

(Image: Twitter/ @capt_navy )

The naval analyst said: “The US can't send submarines in there because the water is too shallow for nuclear-powered submarines (SSNs). A diesel submarine would have to be the one to sneak up there so only NATO countries with SSK's (diesel) could reach the area.

“If a country thinks they have the ability to go in there and spy to see what is going on they might do it.”

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The news comes as the US military asked the State Department to tell Turkey it intends to sail a warship into the Black Sea.

Also, yesterday Ukrainian TV reported NATO has “decided” to send ships to the Sea of Azov, but the decision had not been finalised.

Mr Moreno said it is likely that when NATO sends a surface ship, it will be escorted with one or two submarines for protection and surveillance.

He added: “The Kilo class that Russia sent is probably out there right now. Russia probably has a few SSNs running around the Black Sea as well.

“Probably posted at the inlet of the Black Sea waiting to hear something come in. That warship we are sending in is going to be a sitting duck because there is only one way in and out.”

The submarine analyst claims there is going to be a lot of “cat and mouse” in the region.

(Image: TWITTER )

(Image: GETTY )

He continued: “More than likely a Russian SSN is sitting at the outlet of the Bosphorus strait waiting to tail it.

“They tail the warship we tail the Russian submarine. Welcome to Cold War 2.

“Who knows how it will turn out? Russia may have a wolf pack sitting there waiting to just go active and mess with them the entire trip.

“There may not be a submarine at all. That Kilo could be doing something else.

“Who knows? Thats how great books are written.”