A Ukrainian maritime drone packed with explosives rammed into a Russian oil tanker early Saturday off the eastern coast of occupied Crimea, Russian officials and a Ukrainian official said, the second strike on a Russian ship at sea in two days.
That attack coincided with a new directive from Ukraine’s maritime authority, dated Friday, warning that six Russian Black Sea ports and the approaches to them would be considered “war risk” areas until further notice. The notice expanded on a less specific warning last month that any vessels sailing to ports in Russia or occupied Ukraine would be considered military targets.
Taken together, the tanker attack — which occurred in the Kerch Strait near a critical bridge connecting Russia and the Crimean peninsula — and Kyiv’s new directive have ratcheted up the threat of expanded violence in the Black Sea. Tensions had already been stoked by Russia’s sustained aerial assault on Ukraine’s ports since Moscow decided last month to withdraw from a U.N.-brokered deal allowing Ukrainian grain exports.
The moves fit into Ukraine’s newly emboldened strategy of taking the war into Russian territory, as enunciated recently by the country’s president, Volodymyr Zelensky. It was, “inevitable, natural and absolutely fair,” he said, that the war “is returning to the territory of Russia — to its symbolic centers and military bases.”
This week Ukrainian drones hit a Moscow skyscraper housing government ministries twice within 24 hours. And on Friday, another maritime drone damaged a landing vessel of the Russian Navy near the Russian port of Novorossiysk, a key naval and shipping hub on the northeastern shore of the Black Sea.
A Ukrainian official, speaking on condition of anonymity to discuss a classified military operation, acknowledged that Ukraine was behind Saturday’s attack on the Russian tanker. The vessel was identified by The New York Times as the Sig, which was placed under United States sanctions in 2019 for assisting Russian forces in Syria.
The ship was last tracked to a position about 12 miles south of the Kerch Strait Bridge, in the waterway linking the Sea of Azov and Black Sea, according to recent satellite imagery and marine traffic data.
Russian maritime authorities said the engine room of the oil tanker was damaged in the attack, but that the ship remained afloat. There was no oil spillage and no crew members were injured, it said in a statement on the social messaging service Telegram.
Shortly after the tanker was hit, the crew issued a distress call. “We can’t move on our own without a tugboat,” one crew member said, adding that the cargo tanks were empty, according to audio of the call that was corroborated with ship tracking data by The New York Times. “Machine room is completely flooded.”
According to tracking data from Pole Star, which follows marine traffic, and a photo verified by The Times, at least one tugboat was dispatched to assist.
Russia’s Foreign Ministry immediately denounced Saturday’s strike and promised to retaliate — and by evening Mr. Zelensky reported that Russia had launched new missile attacks on Ukraine.
In his nightly address, Mr. Zelensky said that buildings belonging to an aircraft engine manufacturer, Motor Sich, had been hit in the country’s west. He said the missiles included hypersonic Kinzhal missiles, and Kalibr cruise missiles — some of the most sophisticated conventional weapons in Russia’s arsenal. He added that Ukrainian air defense forces managed to intercept some of them.
Later in the evening, Mr. Zelensky added that Kupiansk, a town in the Kharkiv region of northeast Ukraine, had also been attacked. In a message on social media, he said there had been casualties, but had no further details.
As Ukraine steps up its long-range assaults on Russian targets, officials who once maintained a studied ambiguity regarding strikes in Crimea and Russia have been increasingly taking credit, even if they refrain from explicitly claiming individual attacks.
Vasyl Malyuk, the head of the Security Service of Ukraine, said in a statement on Saturday that Ukraine was responsible for the recent attacks on the Russian ships, calling them a “logical” and “effective” tactic — without specifically mentioning the strike on the oil tanker.
If Russia wants to stop the attacks, he said, “they should use the only option for this — to leave the territorial waters of Ukraine and our land.” His remarks came a day after Ukrainian forces hit the Russian landing ship, the Olenegorsky Gornyak, in the port of Novorossiysk.
The Novorossiysk strike was not expected to have an immediate impact on world oil markets, analysts for the Eurasia Group said in a note on Friday, before the tanker was struck.
But noting that crude exports from Novorossiysk average around 1.8 million barrels a day, or around 2 percent of global supply, the analysts said “the loss of this volume in the current market could push oil prices to over $100 per barrel.”
Britain’s Defense Intelligence Agency said in a statement that the Novorossiysk strike had “seriously damaged” the 370-foot-long landing ship, dealing a “significant blow” to Russia’s Black Sea Fleet.
The agency further noted that Russia had relocated many of its units to Novorossiysk in light of the “high threat” to ships in the port of Sevastopol, which lies on the west coast of Crimea within range of Ukrainian missiles as well as drones.
Kyiv’s increasingly bold strikes at sea come as its forces are waging a slow and bloody counteroffensive to recapture Russian occupied territory in southern Ukraine. Having been repelled by Russian antitank mines and other defenses, Ukraine has shifted strategy to degrading Russia’s fighting capability with strikes on fuel and ammunition depots in Russian-occupied territory. It has achieved no major breakthrough thus far, however.
Victoria Kim, Riley Mellen, Dmitriy Khavin and Gaya Gupta contributed reporting.
