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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Sunshine and showers today, cloudy with rain tomorrow.
Sun and showers today, cloudy with rain tomorrow.
A detective who helped bring the double murderer Christopher Haliwell to justice says he could also have killed Claudia Lawrence.