Ukrainian naval drones attacked Russia's main port on the Black Sea today, Friday, causing damage to a naval vessel, according to a Ukrainian official.

This attack is the latest in a series of strikes within Russia, where Kyiv has vowed to bring the fight home, while Moscow claimed it repelled the attack.

The strike on Novorossiysk marks the first time a Russian commercial port has been targeted in the 18-month-long war, with the port, which hosts a naval base, shipyards, and an oil terminal essential for exports, located across the Black Sea from Crimea, where the Russian Defense Ministry stated it thwarted another attack overnight, shooting down 13 drones.

The Ukrainian security service and navy carried out the attack on Novorossiysk, according to a security official, and the landing ship, Olenegorsky Gornyak, sustained significant damage, resulting in the vessel being unable to perform its combat missions, the official added, speaking on the condition of anonymity as they were not authorized to provide information to the media.

Ukrainian news agencies shared footage from social media indicating it shows the Olenegorsky Gornyak listing to one side. The ship is designed to transport troops and heavy equipment and was sent for repairs in 2014, according to Russian media reports. It is usually based with the Russian Northern Fleet in the Arctic.

However, Russia claimed it repelled the attack on Novorossiysk, stating that the ships patrolling the vicinity of the naval base, including Olenegorsky Gornyak, destroyed two naval drones. The Caspian Pipeline Consortium, which operates the oil terminal at the port, said marine traffic was halted for several hours but its facilities were not damaged, and the regional governor stated there were no injuries.

Kremlin spokesman Dmitry Peskov declined to comment on the attack during a conference call with journalists.

Footage posted on Russian social media apparently showed a ship firing into the sea and an explosion with a burning object. Ukrainian social media also shared nighttime video that it indicated was of a naval drone hovering near a ship. The Associated Press was unable to verify the videos.

Friday's attack is the latest in a series of strikes within Russian territory. Earlier this week, drones hit a building in Moscow, with even a drone striking the Kremlin without causing damage in May.

The attack comes as the Black Sea has become an increasingly important battlefield in the war after Russia withdrew from a deal that allowed Ukrainian grain shipments across the sea. Since the cancellation of the deal, Russia has targeted the country's ports, exacerbating the blow to food markets worldwide.