The Great North Air Ambulance Service (GNAAS) was called to Barnard Castle after a man took unwell on grouse moor.
GNAAS was called to the scene to assist North East Ambulance Service at 2.30pm yesterday, where a man, thought to be in his 60s, became unwell.
The patient was assessed by the doctor and paramedic team before he was taken to hospital for ongoing treatment.