A makeshift shrine has been made to the teenager

Kodjo, of Portland Road, Notting Hill, died after he was stabbed through the heart on Wednesday.

The four youths, two aged 13, one aged 15 and a 16-year-old, are due to appear at West London Magistrates' Court. Five other youths were given bail.

Friends of the victim have left tributes at a makeshift shrine close to where he died in Hammersmith Grove.

'Getting worse'

Kodjo was interviewed about knives on television five days before his death.

He told an MTV programme: "Stabbings are getting worse but the media is also making it bigger than what it is."

Kodjo was also asked about the prevalence of knife crime.

He said: "I don't think it happens all the time but it happens quite a lot."

Detectives searching for the murder weapon have focused on the area around Hammersmith Grove.

Police have said at least 40 people have come forward with information about the attack.