A 23-year-old woman from Ilford has died in hospital after eating a so-called cannabis sweet last week.
The Met is working to identify any other instances of people becoming seriously unwell after eating cannabis edibles or similar products - including a potentially linked case in Tower Hamlets.
Police say the Ilford woman bought what she thought were cannabis sweets - also known as “gummies” - via a messaging app last Tuesday (March 29).
After they were delivered to her home, she and a 21-year-old friend each ate one sweet.
Both women immediately felt unwell, and were taken to hospital after emergency services were called to an address in South Park Drive around 11.30pm that night.
The woman who died - a 23-year-old who police are not naming at this time - passed away in hospital on Saturday (April 2).
Scotland Yard confirmed the other woman was released after receiving treatment.
Police say a post-mortem examination will be arranged and tests are being carried out on sweets seized by officers.
A man from Woodside in Croydon was arrested last Friday - April 1 - and found to be in possession of a large quantity of cash and what were believed to be edible cannabis products.
He was charged the next day with possession with intent to supply Class B synthetic cannabinoid, being concerned in the supply of a synthetic cannabinoid, and possession with intent to supply a psychoactive substance.
There is no indication at this stage that his arrest is linked to the Ilford case or that under investigation in Tower Hamlets.
With respect to the latter, police say they are aware of an instance in March where a woman became unwell and was taken to hospital after eating a cannabis sweet.
The Met is investigating whether this sweet was part of the batch associated with the Ilford death.
Ch Supt Stuart Bell of the Met’s East Area command unit said: "I must warn the public against taking any illegal substances, including those packaged in the form of cannabis sweets.
“Please do not buy or consume these products. They are illegal and, because of the child-friendly packaging, they can pose a risk of accidental consumption.
“The particular batch of sweets were contained in packaging featuring ‘Trrlli Peachie O’s’ branding.
"It has not been confirmed at this stage where the sweets were manufactured."
Anyone with information about the sale of such products is asked to speak with local officers, call 101 or, to remain anonymous, contact Crimestoppers.
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