A Ukrainian naval drone carrying 450 kilograms of TNT struck the Russian Navy base at Novorossiisk in the Black Sea, causing extensive damage to a Russian warship docked there, sources in the Ukrainian Security Service (SBU) told RFE/RL.
Russia's Defense Ministry said earlier on August 4 that its forces had repelled two Ukrainian naval drone attacks on the Novorossiisk base, while Krasnodar regional Governor Veniamin Kondratyev told the RIA Novosti news agency that no casualties or damage were reported from the attacks.
But SBU sources shared a video with RFE/RL purportedly showing the Russian landing ship Olenegorsky Gornyak from the perspective of a camera mounted on a naval drone that ceases its video feed at the moment of the alleged impact. The sources said some 100 crew were on board the ship.
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Ukraine's Naval Drones Seeking To Sink Russian War Effort
"The special operation was carried out together with the navy," one of the sources told RFE/RL.
"As a result, the Olenegorsky Gornyak incurred a large hole and is currently unable to perform its combat tasks. Therefore, all the Russians' statements about the 'repulsed attack' are fake," the source said.
The claim could not be independently verified.
Some posts on social media -- which could not be verified -- showed a ship reported to be the Olenegorsky Gornyak listing severely while being towed.
Ukrainian President Volodymyr Zelenskiy said he had received a report from the head of the SBU but would not comment on its contents.
"I will only say that we are all grateful to the Security Service of Ukraine for returning the war to the aggressor state. What you bring to the world is what you end up with," Zelenskiy said in his evening address.
The attack has reportedly prompted a temporary halting of ship movements in Novorossiisk, one of Russia's main commercial ports.
The Caspian Pipeline Consortium that operates an oil terminal in Novorossiisk said the port authorities have temporarily halted all ship movement, although installations were not damaged and oil loading continued.
The Defense Ministry also said that it had shot down 13 drones over Crimea but that no damage or casualties were reported.
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However, social media posts said that an oil depot in the port of Feodosia caught fire and triggered some explosions.
Following the Novorossiisk and Crimea drone attacks, an air-raid alert was declared for the entire territory of Ukraine around noon.
Attacks in and around the Black Sea have increased since Russia refused to extend a Turkish- and UN-sponsored deal that allowed the shipping of Ukrainian grain by sea.
Russia earlier in the week attacked Izmayil, one of the two Danube ports used by Ukraine to export grain. Izmayil is located just 15 kilometers from the Romanian port of Tulcea.
British intelligence said on August 4 that Russia appears to prefer striking targets close to NATO territory with Iranian-made drones rathar than cruise missiles to avoid the risk of military confrontation with the alliance.
"There is a realistic possibility that Russia is using OWA UAVs (drones) to strike this area in the belief they are less likely to risk escalation than cruise missiles: Russia likely considers them as acceptably accurate, and they have much smaller warheads than cruise missiles," the British Ministry of Defense said in its daily intelligence report.
Zelenskiy said that "very cruel" fighting was under way on the battlefields in the east.
"The occupiers are trying to stop our guys with all their might. The attacks are very cruel," Zelenskiy said, adding that "it is hard everywhere. But whatever the enemy does, it is the Ukrainian force that dominates."
The Ukrainian General Staff on August 4 recorded about 40 battles at the front over the past day, with Ukrainian forces continuing their offensive in the south.
Deputy Defense Minister Hanna Malyar said on August 4 that Ukrainian forces in southern Ukraine had already broken through the first line of defense in some places and moved to the intermediate line.
"And there they face the fact that the enemy has actually built engineering fortifications on...key commanding heights. This, of course, complicates the movement of our troops and combat operations," she said.
Malyar also noted that Russia was shifting reserves both to the south and east, saying these are "mostly professional soldiers."
Pavlo Kyrylenko, the governor of Donetsk, said on August 4 that Russian shelling killed two civilians over the past 24 hours in the region.
Serhiy Lysak, the governor of the Dnipropetrovsk region, said early on August 4 that two civilians were wounded by intense Russian shelling overnight.
Meanwhile, the bodies of 44 Ukrainian soldiers were returned to Ukraine, the Ministry of Reintegration of the Temporarily Occupied Territories reported on August 4. The bodies were repatriated from Russian-occupied territories, the ministry said in a statement.
The bodies will be identified and then handed over to relatives for burial, it said. Last month, the ministry announced the return of 62 bodies of Ukrainian soldiers.