The Olympic Park Aquatics Centre in London has been evacuated after chlorine gas was released, with “multiple” casualties suffering breathing difficulties.

       Emergency services are attending the centre in Stratford’s Olympic Park after the alert was raised at around 10am. About 200 people were inside at the time.

       The area has been cordoned off, and people have been asked to keep away.

       London Ambulance Service said it was responding to a “major incident” at the park with a “number of resources” at the scene. The Metropolitan Police and London Fire Brigade also rushed to the scene.

       Queen Elizabeth Olympic Park said: “We are working closely with emergency services who are on site. We understand there are a number of casualties with breathing difficulties who are being treated by the London Ambulance Service.”

       Recommended Major incident after ‘high quantity of chlorine’ causes casualties - follow live Lloyds, Bank of Scotland and Halifax to shut 60 branches across the UK Hay fever warning as temperatures soar to 21C and pollen levels spike

       Effects of chlorine gas include “irritation of eyes, nose and throat that can usually be tolerated for about an hour”, according to Patient.info, which is certified by the NHS.

       Higher intensities may cause chest pain, shortness of breath, and cough.

       Major incident after ‘high quantity of chlorine’ causes casualties - follow live

       Extremely high concentrations are usually fatal over 30 minutes, it says.

       Footage from the area showed several ambulances parked outside the aquatics centre.

       “London Ambulance Service is responding to a major incident @AquaticsCentre in Stratford alongside colleagues from @LondonFire and @metpoliceuk. We have dispatched multiple resources to the scene and are treating a number of patients. More updates to follow,” London Ambulance Service said in a statement.

       London Mayor Sadiq Khan said: “I remain in close contact with our emergency services who are dealing with a gas-related incident at the London Aquatics Centre this morning.

       “A number of people are being treated by London Ambulance Service. Please avoid the area which has been cordoned off and evacuated.”

       (Thomas Kingsley)

       People living nearby have been asked to keep doors and windows closed.

       Fire chiefs said: “Due to a chemical reaction a high quantity of chlorine gas was released inside the centre.”

       The brigade tweeted: “Update Aquatic Centre in Stratford. Due to a chemical reaction a high quantity of chlorine gas was released inside the centre.

       “While we ventilate the premises we would ask those residents in the immediate vicinity to close their doors and windows.”

       London Fire Brigade said a “high quantity of chlorine gas” was released inside the Aquatics Centre at the Queen Elizabeth Olympic Park in London due to a “chemical reaction”.

       Recommended Major incident after ‘high quantity of chlorine’ causes casualties - follow live Lloyds, Bank of Scotland and Halifax to shut 60 branches across the UK Hay fever warning as temperatures soar to 21C and pollen levels spike

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