Ambulance crews were called to a medical emergency at Oktoberfest Norwich.
The event was shut temporarily as emergency services treated the patient at Eaton Park on Saturday evening.
A statement was released on the Oktoberfest Norwich Facebook which reads: "Unfortunately due to a customer experiencing a medical emergency inside the venue during our afternoon session, we have been unable to open at 18:00 this evening as planned.
"We are currently awaiting an ambulance and as soon as the emergency services give us the all clear, we will open for this evening's session.
"Please accept our apologies and thank you in advance for your understanding."
The extent of any injuries are not yet known.
The organisers then posted at around 6.45pm to say the doors had reopened and the patient safely in the care of paramedics.
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