An air ambulance landed in Colchester Zoo's elephant enclosure to treat a 19-year-old visitor who was suffering breathing problems and had fallen unconscious at the attraction.
Families watched as the Essex Air ambulance made the unusual emergency landing on Sunday morning.
A spokeswoman for the ambulance service told the Ipswich Star: "Landing at the zoo was one of the more unusual places that the aircrew have needed to go.
"The pilots follow strict landing protocol for any site, and this incident involved working closely with zoo staff to ensure the animals and visitors would not have been adversely affected."
According to the Daily Telegraph, the wide and flat space inside the elephant enclosure was believed to be the best place for the aircraft to land.
The four elephants in the pen were moved inside their house before the chopper landed.
The woman was treated at the scene and later taken to Colchester General Hospital.
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