Police have named a man stabbed to death outside a Croydon pub.
Lucas Sutton, 22, was knifed repeatedly in a fight in Mayo Road about 7.45pm on Tuesday.
A 16-year-old boy has been arrested on suspicion of his murder.
The air ambulance and police were scrambled to the scene and paramedics fought to save the victim’s life.
A post-mortem examination carried out on Thursday gave a preliminary cause of death as stab wounds.
Detective Chief Inspector Brian Howie, who is leading the investigation, said: “This is a devastating time for Lucas’ family and my thoughts are with them. We will do everything we can to bring those responsible for his death to justice.
“We believe Lucas was stabbed during an altercation in Mayo Road involving a number of black males who were later seen running away from the area.
“We are making good progress with our investigation and an arrest has been made, however we need to hear from anyone with information about what happened.”
A witness told MyLondon: “He ran into the pub and took his jacket off outside and he had two massive stab wounds to his back.
“He cried out ‘help me help me’ and then collapsed.
“The boy’s mum came later and was just screaming, it’s so sad.”
Chief Superintendent Andy Brittain, local policing commander for south London, said: “First of all, I want to express my sincere condolences to the family and friends of this young man. Our officers are supporting them during this awful time and I want to reassure them, and the local community, that we are committed to bringing those responsible to justice.
“A lot of work has taken place overnight and detectives will remain at the scene throughout the day as they continue to piece together what happened. Local neighbourhood officers will also be in the area to respond to any concerns you may have.”