The strike, which couldn’t be independently verified, killed seven members of the Russian crew and injured six others, while 52 were rescued, the agency said.

The Russian Defence Ministry didn’t comment on the claim, but some Russian military bloggers confirmed the ship’s loss and said its crew had been rescued.

The strike, if verified, would mark the latest successful use of Ukraine’s domestically produced Magura drones, the agile uncrewed boats that have become the Russian navy’s nemesis.

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The Russian military hasn’t acknowledged those losses, either, but they have been reported by Russian military bloggers and some media.

Ukraine claims it is the first country to set up a specific unit dedicated to producing sea drones. Yemen-based Houthis have also deployed armed unmanned surface vessels as suicide drone boats that explode upon impact.

The two-year-old Ukraine conflict has become a laboratory for new military technology, and naval drones are set to become an essential part of the combat toolbox in 21st-century warfare.

Ukraine has loaded them with explosives. The sleek vessels speed across the water’s surface, trailing a wake of white foam, and have a low radar signature that makes them hard to detect.

They are equipped with advanced GPS and cameras.

The Magura V5 sea drone that Ukraine says it used in the Black Sea on Tuesday appears to be Kyiv’s latest version. The craft wouldn’t look out of place in a James Bond movie.

The Magura is 5.5 metres (18 feet) long, weighs up to 1,000kg (2,200 pounds), has a range of up to 800km (500 miles), 60 hours of battery life, and a 200kg (440-pound) payload, according to Ukrainian authorities. It also beams live video to operators.

Another drone that is larger than the Madura, is called Sea Baby.

The latest Sea Baby model is capable of carrying 850kg of explosives, hits a top speed of 90km/h (56mph) and can cover a distance of 1,000km, according to Ukraine’s State Security Service.

Kyiv officials say some 20 per cent of Russian missile attacks on Ukraine are launched from the Black Sea. The Ukrainian fleet lost 80 per cent of its vessels after Russia’s occupation of Crimea in 2014, they say.

Ukrainian naval drones first struck a Russian ship in October 2022, the military claim, when they hit vessels moored off the coast of occupied Crimea.

Last July, Russia said two Ukrainian maritime drones hit the Kerch Bridge, a key supply route linking Russia to Crimea, forcing its temporary closure. Unconfirmed reports said a Sea Baby drone was used in that strike.

The following month, Ukrainian sea drones struck a Russian port and damaged a warship, officials said.

Although the Russian Defence Ministry has mostly kept quiet about the Ukrainian drone and missile attacks on its naval assets, Russian military bloggers and commentators have harshly criticised the military brass for its slow and sloppy response to the threat.

The strikes have forced the Russian navy to take precautions that have affected its operations, including relocating some of its ships from ports in Crimea farther east to Novorossiysk to better protect them.

Putin forced to relocate ships in Crimea after Ukraine strikes

Despite the damage from Ukrainian attacks, the Black Sea fleet remains a powerful force and is still capable of launching long-range cruise missile strikes at Ukraine.

In Ukraine, the daring sea drone attacks have lifted morale.

Ukrainian know-how and ingenuity are behind the development of the new generation of sea drones.

They are locally designed and tested, but some components are sourced abroad.

United24, a government crowdfunding organisation that elicits donations from companies and individuals worldwide, collects the funding.

Though the sea drones aren’t cheap – each Magura, for example, comes in at around US$250,000 and the new model Sea Baby costs around US$221,000 – they can damage or sink a ship worth hundreds of millions of dollars.

United24 says it is assembling the world’s first drone fleet.