A teenager was sprayed with an unknown substance in Kensington Gardens on Wednesday (August 9) morning.
It happened close to Kensington Palace, in The Broadwalk, with the 17-year-old boy taken to hospital as a precaution.
Police were called to the scene at 10.09am and attended along with London Ambulance Service and the fire brigade.
Photos taken at the scene show the youngster being washed by members of the emergency services, with a police officer wearing blue gloves.
The incident follows an alarming increase in the number of attacks involving corrosive liquids thrown at victims.
No arrests have been made, and police enquiries are continuing.
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