Puma Helicopter

We were quietly sitting in the house a little before noon whan we heard the roar of aero engines. As this was a lot louder than usual, I looked out to see a pair of Pumas passing at a very low altitude. Grabbed the camera, ran out and started shooting as the passed over. The shot above was taken with the lens set to 70 mm so they must have been helluva low! They swung round through a tight 360 degrees and finally vanished off to the west.
I wonder what all that was about?
I think that will be our excitement for the day.