A man has been taken to hospital after he was struck to the head with a weapon.
Police, including armed units, say there were called to Stratfield Road, Borehamwood, just before 11.20am to reports of an assault and altercation.
The air ambulance attended too, landing next to Meadow Park.
A man was found injured but police do not believe his injuries are life-threatening.
He has been taken to hospital - the air ambulance took off at 12.30pm - but we don't know if the patient was transported to hospital by air.
Police are treating the incident as isolated as they believe the two men involved know each other.
No arrests have been made.
An armed unit parked up near Borehamwood police station - at least three units attended
Enquiries are ongoing to establish the circumstances around what happened and also to work out what was used to hit the man around the head.
Anyone with any information is asked to contact police on 101 or call Crimestoppers anonymously on 0800555111.
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