A woman and four emergency workers are receiving treatment in hospital after being exposed to a “hazardous substance”.
The woman had been taken to Croydon University Hospital after reports she had ingested poison.
Two Metropolitan police officers and two London Ambulance Service (LAS) staff members were exposed to the substance while responding to the emergency callout. They are now under observation.
A spokesperson for Croydon Health Services NHS Trust confirmed they had “treated a small number of patients, including two police officers, for chemical exposure” after the “isolated incident”.
An LAS spokesperson said that an ambulance crew was dispatched to an address in Thornton Heath at 3.37am on Thursday following reports of a person unwell.
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The woman was then “found to be in possession of a possible hazardous substance”. An incident response officer and a hazardous area response team were also sent to the incident.
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“Two members of staff who initially responded to the patient were treated for exposure to harmful chemicals and are being monitored as a precaution,” LAS said.
A police spokesperson added that the Met was contacted by the LAS 10 minutes after the ambulance crew arrived at the Thornton Heath property.
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They said: “Officers and the London Fire Brigade attended Mayday Hospital and safety cordons and closures were established while specialist officers examined the [hazardous] item and safety procedures were enacted.”
No arrests were made, they added.
The incident has since been stood down, with road closures lifted and all parts of the hospital reopened.