A 21-year-old man died after being stabbed amid crowded scenes at the Notting Hill Carnival on Monday night.
The Metropolitan Police said in a statement that 8pm officers were informed of the stabbing in Ladbroke Grove, under the Westway flyover, at about 8pm.
The victim was provided first aid at the scene before he was taken to a west London hospital by paramedics from London Ambulance Service, the statement said.
"They were able to extract him through significant crowds in challenging circumstances to a waiting ambulance," the police said.
"... Despite the best efforts of medical staff, he was pronounced dead. His next of kin have been informed and are being supported by specialist officers."
Hundreds of people were arrested after "a number of violent incidents and serious stabbings" were reported at the carnival.
According to police 209 arrests had been made by the small hours of Tuesday, including 46 for assault, 36 for possession of drugs, 33 for possession of an offensive weapon, 27 public order offences and eight sexual assaults.
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