A cargo ship and a Russian warship have collided in the Sound in Danish waters, says the Swedish newspaper Aftonbladet.

The cause of the collision is not yet known, but there has been heavy fog in the area, rescue director Jörgen Hansson from the Swedish Maritime Administration told the newspaper.

Hansson is not currently aware of any personal injury or oil spills.

The collision took place in Danish waters, but the Swedish Maritime Administration has also sent its own units.