Grain Tensions Between Ukraine and Poland Escalate: Live Updates

A ship entering the Sulina Canal in the Danube Delta, on its way to port, in Sulina, Romania, last month.Credit…Andreea Campeanu for The New York Times

The crew of a cargo ship sailing across the Black Sea was rescued and evacuated to the Romanian port of Sulina, near the border with Ukraine, after the ship was damaged by an explosion, the Romanian authorities said on Wednesday.

The cause of the explosion remains unknown. Romania’s prime minister, Marcel Ciolacu, suggested in a news conference that the ship could have been damaged by a mine, but did not offer any evidence for the claim. Since the start of Russia’s full-scale invasion of Ukraine in February last year, both countries have littered the Black Sea with explosive devices.

Romania’s transport and infrastructure minister, Sorin Grindeanu, said at the news conference that there were two hypotheses for what could have caused the damage: a sea mine or an explosion in the engine room. Mr. Ciolacu said that the hypothesis about the mine was “closer to the truth,” but he did not elaborate.

Earlier in the day, Romanian media reported that Cosmin Dumitrache, the head of the Romanian Naval Authority, had said that there were “no concrete indications that a mine could be the cause” of the explosion. Investigations about the cause of the explosion were ongoing, the authorities said.

A day before the explosion, a ship loaded with wheat sailed for the first time on a new Black Sea route put in place by Ukraine to circumvent the blockade. Ukrainian authorities hailed the news as proof that ships could navigate safely in and out of Ukrainian waters, but experts cautioned that the risks remained high. The ship damaged on Wednesday was headed for a different route, which circumvents Ukraine’s Black Sea Ports by using the Danube River.

Russia and Ukraine have escalated their fight in the Black Sea in recent months, drawing the war closer to Romania, a member of the North Atlantic Treaty Organization. Russia has targeted Ukrainian ports and grain facilities on the Danube, just across the river from Romania, and Ukraine has battled to control strategic oil and gas platforms in the northwestern part of the Black Sea, a few dozen miles off the Romanian coast.

The fighting has raised fears that it could drag NATO into a direct military confrontation with Moscow. The alliance’s commitment to mutual defense considers an attack on one member as an attack on all. Earlier this month, debris from what Romanian authorities said could be Russian drones was found on Romanian territory, following attacks on nearby Ukrainian ports. But Romania has avoided any suggestion that it might invoke the joint defense pact over the debris.

The explosion on Wednesday caused serious damage to the ship and put it at risk of sinking, Romanian officials said. Mr. Grindeanu said that a tugboat had been deployed to take the vessel closer to shore to prevent it from going down.

Romanian authorities said the crew of the Togo-registered Seama vessel had reported the explosion around 6:50 a.m. local time and that Romanian sea rescuers had picked up the crew members about 30 minutes later. Romanian media reported that one crew member had been injured.

Marius Gelu Roibu, the head of Romania’s sea rescue agency, the M.R.C.C., said in an interview that 12 crew members had been brought to the port of Sulina for medical care.

The MarineTraffic website, which tracks global shipping using satellite data, showed that the ship had departed from the Turkish Black Sea port of Bartin. The Romania Naval Authority said in a statement that the ship was transporting cement and had arrived in the Sulina harbor on Sept. 12.

The explosion occurred while it was waiting near the maritime border between Romania and Ukraine, about seven nautical miles east of Sulina, to enter the Bystroe Canal that connects the Danube delta to the Black Sea. It remains unclear whether the ship had entered Ukrainian waters when the explosion occurred.

Ukraine has increasingly used the Danube River as an alternative waterway to trade internationally because of Russia’s attempted blockade of the sea.

Romania’s defense ministry said in a statement that it had dispatched a minesweeper, a warship designed to remove naval mines, to the area, with divers who specialize in explosive devices. The Romanian news agency Agerpress reported last month that, since the start of the war, Romanian naval forces had neutralized five sea mines that had strayed into Romanian waters.