A US-sanctioned Russian cargo ship sank in the Mediterranean overnight after an explosion rocked its engine room, the Russian Foreign Ministry confirmed.

Two members of the Ursa Major are still missing after 14 crew members were rescued and taken to Spain following the explosion on Tuesday morning.

Video footage showed how the 466-foot-long ship swayed heavily on the journey between Spain and Algeria and its stern was much lower in the water.

The boat’s operator, Oboronlogistika, which was sanctioned by the U.S. Treasury Department in 2022 for ties to the Russian military, previously said it was en route to the Russian port of Vladivostok using cranes.

However, the company did not comment on the explosion. The Russian Foreign Ministry did not provide any information about the cause of the engine room explosion.

State news agency RIA quoted the Russian embassy in Spain as saying it was investigating the circumstances of the sinking and was in contact with authorities in Spain.

The ship left St. Petersburg on December 11 and was last seen sending a signal between Algeria and Spain, where it sank, around 10 p.m. on Monday, according to ship tracking data.

It was in the same Mediterranean area as another sanctioned Russian ship, Sparta, when it ran into trouble and the two ships were spotted transiting the English Channel last week, reportedly under escort.

Earlier this month, Ukrainian Military Intelligence (HUR) reported that the Sparta was heading to the Russian naval base on the Syrian coast in Tartus to transport military equipment from Syria following the overthrow of Bashar al-Assad.

A Kremlin official said on Monday that Russia was in contact with Syria’s new rulers at both diplomatic and military levels about the future of its two military facilities.

Ursa Major’s owner, Oboronlogistika, has been heavily involved in transporting cargo to Tartous, Syria in the past.

Syrian bases and the port of Tartus have become crucial to Moscow’s operations in the Mediterranean and Africa, and the fall of Assad has caused major logistical problems for the Kremlin.

Russian operations in countries such as Libya, Mali, the Central African Republic and Burkina Faso relied heavily on the port and Khmeimim air base as a stopover and refueling station.