A man who was stabbed to death in south London has been named as Jaden Christie.
The 20-year-old died at the scene in Stockwell Road, Lambeth, just before 15:00 BST on Tuesday.
A 22-year-old man has been arrested on suspicion of murder after he voluntarily attended a police station, the Met said.
Det Ch Insp Rob Pack said: "Jaden's loved ones are devastated. We are doing everything to work out what happened."
Detectives are urging witnesses to come forward.
Colin Wingrove, from the Lambeth and Southwark basic command unit, said: "This is a horrific incident and our thoughts are with the victim's family, who have lost a loved one in such tragic circumstances.
"I want to reassure local residents that they can expect to see an increased policing presence in the area this evening and over the coming days."