A suspected attacker was chased down and restrained by members of the public following a fatal stabbing near a north London football club.
The Metropolitan Police said they were called to Houndsfield Road in Edmonton at 8.10pm on Saturday to reports of a stabbing.
The London Ambulance Service also attended, but the 29-year-old man who had been stabbed died at the scene shortly after 9pm.
Scotland Yard said the attack happened near to the Old Edmontonians FC clubhouse, which was hosting a party at the time.
Detective Chief Inspector Paul Considine appealed for witnesses, saying: “Lots of people were out and about.
“Members of the public pursued and detained a male suspect following this attack in a nearby field.
“He was subsequently arrested by police.
“I need all those present to call police with information about what they saw take place.”
Police said the attack is not thought to be connected to the event or the football club.
A 40-year-old man has been arrested and is currently in hospital, police said. Officers are not looking for anyone else.
Mr Considine, from the specialist crime unit, said: “We are in the process of gathering witness statements and reviewing local CCTV footage.
“Please do call us with any information you have.”
The Met said specialist forensics teams are still at the scene of the attack.
The victim’s next of kin have been informed and a post-mortem examination is due to take place on Monday.
Anyone who witnessed the incident is asked to call police on 020 8345 3865. To remain anonymous call the charity Crimestoppers on 0800 555 111.