A man who was stabbed to death at a shopping centre close to the Olympic Park in east London has been named as Liam Woodards.
The 24-year-old lived locally in Stratford, Scotland Yard said. No further details were given.
The victim was knifed after a fight broke out between a large group of males at Westfield on Friday afternoon.
Mr Woodards was pronounced dead at the scene and a post mortem examination later revealed that he died from a stab wound.
Two other males suffered minor injuries during the attack, which happened in a busy area of the shopping centre called The Street.
Five men, aged between 20 and 23, were arrested in connection with the death.
A Scotland Yard spokesman said that one, aged 23, had been cautioned for affray and released with no further action. The other four remain in custody.
Detectives have appealed for shoppers or anyone who witnessed the incident to come forward with information.
Acting Detective Chief Inspector Andy Kelly said: "We believe that shoppers at the centre may have filmed or photographed some part of the incident on their mobile phones.
"We encourage them to come forward and share this potentially vital material with us."
A spokesman for the shopping centre, which opened nine months ago, said: "Westfield is working closely with the police and emergency services", but would not comment further.
:: Any witnesses or anyone who can assist should call the incident room on 0208 345 3775 or Crimestoppers anonymously on 0800 555 111.