The UK-led Joint Warrior 2014, Nato's biggest military exercise, has started off the coast of Scotland.
Maritime forces from a host of Nato nations, including 22 ships and submarines and 52 fixed wing aircraft, are taking part in the exercise, which aims to enhance combat skills.
It will involve air, surface and underwater threat training, starting with military and political tension, in addition to simulated war fighting.
As part of the two-week drill, personnel will act in response to a range of modern, realistic simulated scenarios, including anti-submarine warfare, anti-surface warfare, mine countermeasures, live firing and counter-smuggling and counter-insurgency, as well as electronic warfare and logistics support.
It also includes GPS denial operations, which will be executed in a confined area in north-west Scotland.
The UK's Typhoon and Tornado GR4 aircraft will operate from RAF Lossiemouth, together with host fighter planes from Sweden, Belgium, and Germany.
Participating nations include the UK, the US, the Netherlands, France, Denmark, Norway, Spain, Germany, Lithuania, Belgium, Poland, Estonia, and Latvia
The US Navy's Commander Destroyer Squadron 26 has overall command of the task group.
Image: The Belgian Navy's Tripartite-class minehunter BNS Crocus M917. Photo: courtesy of the Royal Navy.