Officers say they were threatened by a man with a firearm.
The injured man is under arrest and in a stable condition in hospital.
We have referred the matter to the IPCC and will support them in their investigations."
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Hotter again on Monday with temperatures up to 25 degrees. Cooler on the coast and on the Isles of Scilly.
A clear night, hotter again on Monday.
Highs this afternoon of around 23 or 24 degrees. Cooler on the coast.