Russians join Nato submarine rescue drill
8 June 2011 Last updated at 07:07 BST
The world's largest submarine rescue exercise, involving more than 20 nations and 2,000 people, is under way off the coast of Spain.
For the first time ever, a Russian submarine is taking part in the exercise, carrying out test dockings with Nato rescue vehicles.
The BBC's Sarah Rainsford was given rare access to an American rescue module on a journey to the bottom of the sea and the Russian submarine, the Alrosa.