Emergency services were called to the south west London venue – formerly the Millennium Dome – at 8.30pm after ammonia gas leaked into the arena where staff were dismantling stage equipment.

Four fire engines and several support units from five fire stations in Greenwich and the surrounding area attended the scene.

At 8.45pm, fifteen ambulances and five vehicles from the London Ambulance Service’s Hazardous Area Response Team were also called to The O2.

Twenty-nine people were taken to hospital suffering from symptoms such as nausea, difficulty breathing and eye irritation but were all treated and discharged the same night. No members of the public were affected.

Firefighters vented the arena after the gas was detected and left the scene shortly after 11pm, allowing the venue to reopen on Tuesday.

A statement released by the managers of The O2 said: “On Monday night there was a minor ammonia leak at The O2.

“The building was immediately evacuated and some members of staff were taken to hospital as a precautionary measure.

“There were all discharged the same night and The O2 opened the following day as usual.

“We would like to thank our staff who responded to the incident in an exemplary way, working with the London Fire Brigade, Metropolitan Police and London Ambulance Service to ensure the safety of everyone in the building.”

Exposure to ammonia gas typically causes irritation to the nose, throat and respiratory tract, and can cause alkali burns in the lungs. In large doses, exposure can cause death within minutes.

The gas is believed to have leaked from the ice rink plant room, but an internal investigation is being carried out into the cause of the incident.

Kate Martin

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