The air ambulance was called after a 70-year-old man fell from a ladder in the Uckfield area.
The Helicopter Emergency Medical Service (HEMS) assisted with treatment at the scene and the patient was taken to the Royal Sussex County Hospital, Brighton, by road.
South East Coast Ambulance Service were also at the scene of the accident which happened on Monday morning.
The man suffered injuries to his head, thorax and abdomen.
*The Kent, Surrey and Sussex air ambulance is not part of the NHS and is almost completely funded by by individuals, businesses and charitable organisations. Read more about the service here (external link).
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