Nine children and two adults were taken to hospital after too much chlorine was released into a swimming pool.
Around 150 people left Vale Farm Sports Centre in Watford Road, Wembley, at 1.40pm today (August 29) after the incident, described by emergency services as a chemical leak.
The operator of the centre, Everyone Active, says "excess chlorine" was released into the pool and that it will be carrying out a full investigation.
The London Fire Brigade said its crews carried out a sweep of the building and found a chlorine leak in a learner pool on the ground floor of the three-storey building.
It added that firefighters ventilated the area and monitored fume levels until there were no high readings.
The London Ambulance Service has confirmed that it treated nine children and two adults at the scene before taking them to hospital. Their condition is not known at this time.
Chris Williams, Everyone Active area contract manager, said: “Some customers were taken to hospital as a precaution, and no colleagues were injured. The incident was isolated to the pool area, but we closed the whole building as a precautionary measure.
“Safety is our top priority and we are taking this incident very seriously. We are conducting a full investigation into the cause and will implement necessary measures to prevent similar occurrences in future.
"We sincerely apologise to all affected customers and will provide an update as soon as we can.”
Mr Williams added that the centre reopened at 4pm today and the pool will reopen at 6.30am tomorrow, after thorough safety checks.
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