Watch: Ukrainian Sea Drone In Direct Hit On Docked Russian Submarine

In what appears an unprecedented first of the war, Ukraine is touting that it deployed a new underwater drone, named “Sub Sea Baby”, to sink a Russian Kilo-class submarine docked at the Black Sea Novorossiysk port.

While not specifying the date and time of the attack, the Security Service of Ukraine (SBU) said Monday the operation was a success as it struck the “Russian submarine of the class 636.3 ‘Varshavyanka’” and as a result it “suffered critical damage and was actually put out of action.”

The SBU further called it the first attack of its kind, describing the joint operation with the Ukrainian Navy, and shared video showing a large explosion at the sprawling Russian port, home to a number of naval assets.

“This class of submarine is also known as the ‘Black Hole’ due to the hull’s ability to absorb sound and remain inaudible to sonar,” the SBU said of the destroyed vessel.

Kyiv Post writes, “The SBU estimated the submarine’s cost at about $400 million, rising to as much as $500 million to replace due to sanctions, and said it can carry up to four Kalibr cruise missiles used in attacks on Ukrainian cities.”

Ukrainian Navy spokesman Dmytro Pletenchuk said that given submarines are understood to be among the hardest targets to hit, the operation marked “another turning point” in the naval battle between Ukraine and Russia.

“This day once again upends the perception of the possibilities of naval combat in this war,” he said according to Reuters.

War monitors estimate that four submarines were stationed in Novorossiysk at the time of the attack, and now one is likely totally disabled, and immediate repairs would be risky as the port is still exposed to further sea or aerial drone attack.

Ukraine is currently seeking to claw back some leverage amid efforts to reach a peace deal with Russia. Ukrainian and US delegations are meeting in Berlin this week in order to hash out what might be acceptable compromise.

News: Ukrainian SBU special operation has hit a $400mn Russian submarine in Novorossiysk.

The Security Service of Ukraine conducted what it called a “unique special operation” targeting the port of Novorossiysk. “For the first time in history, underwater ‘Sub Sea Baby’ drones… pic.twitter.com/5ogO5dwJkx

— Christopher Miller (@ChristopherJM) December 15, 2025

Russia has been absorbing serious blows of late due to Ukraine’s drone warfare, especially at oil refineries and transport hubs; however, President Putin has still shown no signs that he intends to back down from pursuing the goals of the ‘special military operation’.