A number of children were among 24 people who needed hospital treatment following a chemical incident at a hotel spa.
More than a dozen firefighters were involved in a rescue and clean-up operation.
So what happened, and how did the incident unfold?
Here is everything you need to know.
The emergency incident took place after two chemicals were accidentally combined, creating the noxious gas.
The leak sparked a ‘large-scale’ response from emergency services, with eight ambulances scrambled alongside more than a dozen firefighters, and a specialist hazardous materials team.
A spokesman for Hampshire and Isle of Wight Fire and Rescue Service (HIWFRS) said chlorine gas had been accidentally created in the spa area of the hotel.
The Hazardous Area Response Team (Hart) and firefighters from Hightown, Fareham, Cosham, Portchester, St Mary’s and Romsey attended the scene, as well as crews from South Central Ambulance Service (SCAS).
The spokesman said emergency crews were called following reports that a number of hotel guests had been “overcome by fumes in the spa area after two chemicals had accidentally been mixed together and created chlorine gas.
“Hampshire and Isle of Wight Fire and Rescue Service began immediate emergency care, set up a casualty handling area and requested the ambulance service to attend.
A ventilation fan was used to clear the fumes and firefighters took the vessel containing the chemicals to fresh air - gas monitors were then used to check that the scene was safe.
An SCAS spokeswoman said 24 patients “ranging from children to those in their 50s” were assessed and treated by ambulance teams for breathing difficulties.
“Following treatment at the scene by our crews, those patients were taken to University Hospital Southampton for further assessment for those non life-threatening injuries.”
The four-star award-winning spa boasts eight treatment rooms; its hotel accommodation ranges from £130 a night in one of the site’s “signature rooms”, to £205 a night for a premier room.
What happens now?
The emergency came to an end at 1.27am.
The hotel’s general manager, George French, has insisted an investigation has been launched to find out how the leak took place.
In a statement today, he told The News: “We evacuated all guests from the hotel on the instruction of the fire service and have been cooperating with them throughout the night and continue to do so.
“Unfortunately, some of our guests who had been using the spa facilities yesterday evening were taken to hospital as a precautionary measure.
“Our main priority is our guests’ and team members’ health and wellbeing and we will share further information as soon as it becomes available.”
On the venue’s website, the hotel insists “safety” is a top priority and that staff follow all coronavirus guidelines.
“Whilst many visible signs of our safety measures have now been removed, we want you to feel reassured that your safety and our team member’s safety are of utmost importance.
“We continue to operate in a very safe way – a way which has become the new normal for us and we continue to follow the government guidelines which can be seen here for overnight stays and here for dining and drinking.”
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