The air ambulance was called to an incident near Sudbury.
A helicopter from the Essex and Herts Air Ambulance was spotted at Sudbury Rugby Club in Great Cornard at about 5.10pm on Wednesday (August 23).
An eyewitness said the ambulance service was also seen in Topsfield in Great Cornard.
The nature of the incident is currently unclear.
The East of England Ambulance Service has been approached for comment.
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