MOSCOW, Russia (AFP) — Two crew members are missing after a Russian defense ministry-owned cargo ship sank in international waters in the Mediterranean following an explosion on board, Moscow said Tuesday, giving few details on the ship’s mission or what caused the deadly incident.

The Ursa Major sank “after an explosion in the engine room,” the Russian foreign ministry’s crisis unit said on Telegram. It added that out of the 16 Russian crew members, 14 had been rescued and taken to the Spanish port of Cartagena and two were missing.

The Ursa Major is listed on MarineTraffic.com as a 124.7-meter long general cargo ship that was sailing from the Russian city of Saint Petersburg to Vladivostok in Russia’s Far East.

Russian transport investigators announced they had opened a probe into the “incident” over possible maritime safety violations, without giving details.

The ship sent a distress call Monday morning from off the coast of southeastern Spain in bad weather, reporting it was listing and sailors had launched a lifeboat, Spain’s sea rescue service said in a statement.

Spain sent out a helicopter and rescue boats and took the survivors to port, the service said.

A Russian warship then arrived and took charge of the rescue operation since the ship was between Spanish and Algerian waters, after which the Ursa Major sunk overnight.

“According to the survivors’ account, the cargo ship was carrying empty containers in the hold and two cranes on deck,” the Spanish rescue service said.

The ship is owned by a subsidiary of Russia’s Oboronlogistika, which belongs to the defense ministry and also provides civilian transport and logistics, the Russian foreign ministry said.

The United States in 2022 imposed sanctions on Oboronlogistika and ships including the Ursa Major for providing “transportation services...for the delivery of cargo to Russian-occupied Crimea.”

This means any United States organization dealing with the company or its ships would risk sanctions.

Ukraine’s GUR military intelligence said the Ursa Major was also used to supply Russian troops in Syria where Moscow has a naval base at Tartus.

A map on Oboronlogistika’s website shows the company among other things covers a route to Tartus from Novorossiisk, in southern Russia.

Russia ‘evacuating weapons’

The incident came amid uncertainty over the future of Russia’s bases in Syria — the naval base in Tartus and Hmeimim air base — after the removal of Moscow ally Bashar al-Assad.

These are Russia’s only military outposts outside the former Soviet Union and have been key to the Kremlin’s activities in Africa and the Middle East.

Moscow has “contacts” with Syria’s new authorities, “including on a military level” but “much is unclear so far,” Kremlin aide Yury Ushakov said Monday.

“Russia has begun transporting some of its weapons and equipment from the port of Tartus to Libya by sea,” Ukraine’s GUR military intelligence service said Monday.

The Ursa Major entered the Mediterranean along with four other Russian ships including three warships, Russian independent news website The Insider reported Monday.

Last week Oboronlogistika issued a press release with photos of the ship in port, saying it was to transport a particularly large and heavy load: cranes each weighing 380 tons and hatch covers for icebreakers each weighing 45 tons to Vladivostok.

This was part of “state” efforts to develop ports and the northern sea route via the Arctic, Oborono said.

Delivery by sea is best for such bulky equipment and the company has “great experience” in this, it said.

Agentstvo investigative news site wrote that the hatch covers were for a vaunted new nuclear icebreaker called Lider, designed to break thick ice on the northern sea route.

The accident came after a Russian tanker transporting fuel oil partially sunk in a strait between Moscow-annexed Crimea and southern Russia on 16 December, causing a major oil spill.