Satellite images show Russia fortified a port against Ukrainian drone boats. One broke through underwater and exploded.

• Ukraine said on Monday it carried out an underwater drone attack on a Russian submarine in its port.

• New satellite images show damage to the port of Novorossiysk following the explosion.

• The images also show that Russia tried to fortify the port in advance to defend against a Ukrainian attack.

Newly captured satellite images show the aftermath of a Ukrainian drone attack on a Russian submarine at a Black Sea naval base.

New images captured by U.S. space intelligence company Vantor on Tuesday and obtained by Business Insider show damage to part of a dock next to a Kilo-class submarine in the port of Novorossiysk.

Ukraine’s internal security agency said on Monday it used an underwater drone to attack a Russian submarine in a port, the first such attack. Kiev released video of the operation, which triggered a massive explosion in the port, and said the ship was damaged and crippled.

Russian state media reported late Monday that the attack failed to damage a single submarine, citing the Black Sea Fleet.

Satellite images do not appear to show any obvious damage to the submarine; however, there may be some problems beneath the surface, making it difficult to determine whether the operation was successful.

Russia’s Kilo-class submarines are diesel-electric submarines that have been in service since the 1980s and were used to carry out Kalibr cruise missile attacks on Ukraine, making them high-value targets for Kiev.

The new images also show floating barriers at the port’s entrance, a tactic used by Russia to protect its warships and infrastructure from Ukrainian naval drone attacks. However, this defense is primarily against surface threats, as underwater drones are still able to enter ports and cause explosions.

Ukraine has used its fleet of explosive-laden naval drones and long-range missiles to damage and destroy dozens of Russian warships and vessels since the full-scale invasion began.

This asymmetrical operation forced Russia to move its Black Sea Fleet from its long-standing headquarters on the Crimean peninsula to Novorossiysk on the other side of the region. However, Ukraine continues to prove that it can target this port as well.

This latest attack on the Black Sea Fleet appears to mark a new chapter in drone warfare. Ukraine relies primarily on surface naval drones to target Russian warships.

The use of underwater drones represents a significant expansion of Ukraine’s capabilities compared to slow-moving mines or torpedoes and could pose a new threat to the Black Sea Fleet.

Russia once docked its Kilo-class submarines in Crimea but moved them to Novorossiysk several years ago due to Ukrainian strikes, conflict analysts at the U.S. think tank the Institute of War wrote in a battlefield assessment on Monday.

Analysts said the recent underwater drone strikes “demonstrate that the Ukrainian military continues to modernize and optimize its unmanned capabilities, allowing Ukraine to strike Russian military targets within ranges that Russian forces previously considered safe.”

Read the original article on Business Insider