Detectives are renewing appeals for witnesses and information following a fatal stabbing in Wandsworth.
Police were called to Deeside Road, SW17 at 16:42hrs on Friday, 14 June following reports of a man stabbed.
Officers and the London Ambulance Service attended and found an 18-year-old man in a critical condition. He died at the scene a short time later.
He has been formally identified as Cheyon Evans from Tooting.
A post-mortem examination took place at St George’s Hospital on Sunday, 16 June and gave the cause of death as a stab wound to the chest.
The investigation is being led by detectives from the Homicide and Major Crime Command
Detective Chief Inspector Helen Rance, from the Homicide and Major Crime Command, said: “Our investigation into the tragic death of a young man continues and my team are working around the clock to establish what happened that afternoon.
“Although we have now made seven arrests, we need to hear from anyone who has any information that will help us. This murder took place in broad daylight on a heavily populated estate; I am sure that there are people who saw, or heard something, but who are yet to come forward.
“It is vital that we piece together the events that led to Cheyon losing his life. Together, the police and the local community can find the answers that his family so desperately need. Please phone us.”
Anyone with information is asked to contact the incident room on 020 8721 4266 or via 101 quoting reference CAD 5877/14June.
Alternatively, they can call Crimestoppers anonymously via 0800 555 111.
Six males were arrested on Friday, 14 June on suspicion of murder.
A 17-year-old boy from Merton and an 18-year-old man were charged on Sunday, 16 June with murder.
Four others have been released under investigation.
A 20-year-old man who was arrested on suspicion of murder on Monday, 17 June has been bailed to a date in mid-July.