Herts Police have been clearing an area around Watford Junction in response to an emergency.
The force confirmed they are at the scene of an “ongoing medical episode” amid a major emergency services response in Station Road.
A spokesperson said that officers are there to help clear the area for the air ambulance to land.
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According to those at the scene, an Essex and Herts Air Ambulance circled above the station for around 10 minutes, during which time it appeared to be looking for somewhere to land.
At around 3.40pm, it landed in Radlett Road Playing Fields, a few minutes away – at least temporarily.
Hertfordshire County Council Highways has warned locals to “avoid the area” as there are delays in the area due to the “emergency services incident”.
It added that a bus diversion is in operation.
Borough councillor Charlotte Saunders, who was nearby at the time and saw the helicopter land, said that she was glad to see that the emergency services appeared to have responded quickly.
“I’m wishing that everybody is ok in the situation,” she added.
This is a breaking news story and will be updated.
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