Ukraine Says It Just Launched First-Ever Underwater Drone Strike To Target Russian Submarine

Ukraine has claimed it carried out a first-of-its-kind attack on a Russian submarine using underwater drones, marking a significant escalation in the use of uncrewed systems in naval warfare.

In a statement on Monday, Ukraine’s Security Service (SBU) said it conducted a “unique special operation” to strike a Russian Kilo-class submarine at the Black Sea port of Novorossiysk. The agency said the attack damaged and disabled the vessel.

According to the SBU, the operation involved its “Sub Sea Baby” drones — an underwater variant of the Sea Baby naval drones that Ukraine has previously used to target Russian surface ships and port infrastructure. The security agency said the submarine was equipped with four launchers for Kalibr cruise missiles, which

Russia has regularly used in strikes against Ukrainian cities.

While the SBU did not disclose the exact timing of the operation, it said the strike was carried out in coordination with the Ukrainian Navy. Footage released by the agency appears to show an underwater drone striking the submarine, triggering a large explosion.

There was no immediate response from Russia’s defence ministry or its embassy in the United States to requests for comment.

Kilo-class submarines are diesel-electric vessels that have been in service since the 1980s and form a key part of Russia’s naval capabilities. Moscow operates dozens of such submarines, making up one of the world’s largest submarine fleets. The SBU estimated the cost of a Kilo-class submarine at around $400 million, noting that international sanctions would significantly complicate and increase the cost of any replacement.

The attack is the latest blow to Russia’s Black Sea Fleet. Since the start of the war, Ukraine has used missiles and drones to damage or destroy dozens of Russian warships, forcing Moscow to relocate much of its fleet from occupied Crimea to Novorossiysk. Kyiv has repeatedly shown it can strike Russian vessels even at the relocated base.

More broadly, the strike appears to signal a new phase in drone warfare. While Ukraine has previously used naval drones against surface ships and underwater drones against Russia’s so-called “shadow fleet” oil tankers, targeting a submarine represents a notable expansion of its uncrewed combat capabilities.