Military jets have been spotted circling the skies above Tayside and Fife as part of a training operation.
Vapour trails could be seen across the region on Wednesday.
Locals told of seeing the planes making sharp turns as they flew above the North Sea approaching Dundee.
Data from flight tracking website Flightradar24 showed several aircraft involved in similar manoeuvres in both Scotland and England.
The planes are taking part in an RAF-sponsored exercise known as Cobra Warrior, which brings together a number of international participants.
United States Air Force F-16s and aircraft from the German and Italian militaries have all been taking part in the exercise, which is due to end on Friday.
The exercise is based out of RAF Waddington near Lincoln and has operated along most of the east coast of the UK throughout this month.
A number of planes owned and operated by private defence contractors are also involved.
These contractors provide airborne training exercises to help pilots prepare for real-life combat situations where they may have to intercept aircraft.
Meanwhile larger refuelling jets from the RAF and US Air Force are also flying over the North Sea.
Wing Commander Abbott, Officer Commanding 92 Squadron, is running the exercise with the RAF’s Air and Space Warfare Centre.
He said: “Exercise Cobra Warrior is the most important exercise that the RAF runs here in the UK and provides us with the opportunity to work with key Nato allies in a simulated contested and degraded operational environment that synchronises multi-domain effects.
“It is only by doing this that our aviators are able to learn and maintain the highly complex skills that are required to conduct such operations now and in the future as part of a coalition.”
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