An engine room explosion sank a Russian cargo ship called Ursa Major in the Mediterranean Sea between Spain and Algeria and two of its crew are missing, the Russian foreign ministry has said.

The vessel, built in 2009, was controlled by Oboronlogistika, a company that is part of the Russian defence ministry’s military construction operations, which had previously said it was en route to the Russian far-eastern port of Vladivostok with two giant port cranes lashed to its deck.

The foreign ministry’s crisis centre said in a statement that 14 of the ship’s 16 crew members had been rescued and brought to Spain, but that two crew were still missing. It did not say what had caused the explosion.