A Russian nuclear submarine has caught fire in a shipyard, according to news agency RIA Novosti.

The Zvyozdochka shipyard is in Russia's northern province of Arkhangelsk.

The information was revealed by a Russian police source, and there are currently no reports about casualties.

The shipyard said it had no comment to make at present about the ship which is presently in dry dock.

Reports suggest the boat is a nuclear propelled, rather than nuclear-armed sub.

The weapons were apparently taken off the submarine before the repair works were started.

The ship reportedly caught fire as welding works were being carried out, with rubber insulation catching fire.