A 36-year-old man is in a critical condition after he came "into contact with chemicals" at an address in Mitcham.
UPDATE: Man dies after "coming into contact with chemicals" at Carshalton Road home in Mitcham
Police shut Carshalton Road after the man fell ill in the early hours of this morning.
He was taken to a south London hospital by paramedics and remains critically ill.
A Metropolitan Police spokesman said officers were searching a property in Carshalton Road, near the junction with Goat Road, after being called at 3.45am.
He said: "It was reported that the man had become unwell having come into contact with chemicals."
There is "no evidence to suggest the incident is linked to extremism or terrorism," the spokesman added.
London Fire Brigade sent two engines, two rescue units and a decontamination team after being called at 3.52am to assist police.
Firefighters from Mitcham station spent nearly four hours at the house.
A London Fire Brigade spokesperson said its detection equipment had not found raised levels of any chemicals so handed it over to the police.
A police spokesman said: "Police officers are carrying out searches at residential premises in Carshalton Road, Mitcham. Local roads are closed in the area.
"Enquiries continue. We are not aware of anybody else injured or taken ill."
Transport for London warned bus routes 127 and S1 were being diverted this morning while Carshalton Road remains closed.
Buses in both directions have been affected.
Do you know more about this story? Call the newsdesk in 0208 722 6337 or email pippa.allen@london.newsquest.co.uk
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