Russian Cargo Ship Ursa Major Sinks Off Spain After Engine Room Explosions

The Russian cargo ship Ursa Major sank a little before midnight on 23 December 2024, 62 nautical miles off the coast of Murcia, Spain. The 142-metre-long Russian-flagged vessel, owned by the state-linked Oboronlogistics company, had been sailing from St Petersburg to Vladivostok. It now lies at a depth of 2,500 metres.

53pm on 23 December 2024. The crew told rescuers there had been three explosions in the ship’s engine room. Other vessels observed that the Ursa Major had slowed dramatically over the previous 24 hours before the distress call and was listing badly with crew abandoning ship.

07pm on 23 December 2024 when a Russian warship arrived, took over operations and ordered the two Sasemar boats to withdraw to a distance of two nautical miles. The Russian warship then launched flares over the Ursa Major. Four similar seismic signatures, the pattern of which resembled underwater mines or overground quarry blasts, were heard just after the flares were fired, according to a CNN investigation.

20pm the Ursa Major had sunk. Two crew members are thought to have died in the initial explosions while 14 were rescued. The vessel was officially transporting non-dangerous merchandise including 129 shipping containers, two cranes, and two large maintenance hole covers.

Under questioning the captain of the Ursa Major told Spanish investigators that the manhole covers onboard were nuclear reactor components similar to those used by submarines but that no nuclear fuel was being transported. Investigators noticed two huge blue containers each estimated to weigh about 65 tonnes on the stern of the Ursa Major in satellite photographs.

A source familiar with the investigation told CNN that the Russian captain believed he would be diverted to the North Korean port of Rason to deliver the two reactors.

A 50cm by 50cm hole was found in the vessel’s hull with the damaged metal facing inwards. The source familiar with the investigation said it concluded the use of a supercavitating torpedo would fit with the size of the hole in the Ursa Major’s hull and that it could have made a noiseless impact resulting in the sudden slowing of the boat on 22 December.

CNN and La Verdad reports documented both the hole dimensions and the inward-facing damaged metal.

US nuclear sniffer aircraft overflew the scene of the Ursa Major wreck twice in the past year. A Russian spy ship set off four further explosions in the wreckage a week after the Ursa Major sank. A report by Oboronlogistics claimed that the Ursa Major fell prey to a targeted terrorist attack.

The Ursa Major set sail two months after North Korean leader Kim Jong-un sent troops to assist with Vladimir Putin’s invasion of Ukraine. A report in the Murcia newspaper La Verdad said the flares could have been deployed to blind the infrared channels of the intelligence satellites monitoring the incident.

The Spanish government document detailing the rescue and Russian warship intervention was released three months ago in response to parliamentary questions over the incident.

CNN suggested the sinking of the Ursa Major may mark a rare and high-stakes intervention by a western military to prevent Russia from sending an upgrade in nuclear technology to North Korea.