Ukraine’s Military Intelligence (HUR) said Thursday its special forces struck and disabled a high-value Russian Black Sea Fleet vessel near Novorossiysk in a drone attack.

The agency said the Sept. 10 strike hit a Project MPSV07 multipurpose support ship, one of only four in Russia’s fleet. Commissioned in 2015, the ship is worth an estimated $60 million.

The drone targeted the vessel’s bridge, destroying its navigation and communications systems and knocking out its electronic surveillance equipment.

The ship was forced out of service and will require expensive repairs.

At the time of the attack, the Russian vessel was carrying out electronic reconnaissance and patrolling approaches to Novorossiysk Bay, where Moscow has redeployed much of its Black Sea Fleet after repeated Ukrainian strikes in occupied Crimea.

Ukraine has intensified its use of domestically produced sea and aerial drones in the Black Sea, claiming a series of successful attacks against Russia’s navy over the past year.

The strike comes days after Ukraine’s Defense Intelligence Directorate (HUR) released video of another operation carried out by its “Prymary” special group in occupied Crimea.

On Sept. 1, Ukrainian drones hit a Russian airbase in Hvardiiske near Simferopol, destroying at least two Mi-8 combat helicopters valued at $20 million to $30 million, officials said.

An equally damaging blow was a strike on a Russian military tugboat, believed to be the BUK-2190, in Sevastopol Bay.

Ukrainian intelligence said the vessel belonged to Russia’s elite PDSS underwater sabotage unit, which includes diver-reconnaissance specialists trained over years at significant cost and equipped with advanced gear.

“The destruction of the tugboat significantly limits the combat capabilities of the elite Russian unit,” HUR said in a statement.