A third teenage boy has been charged with the murder of a 15-year-old who was stabbed to death as he arrived at school, police have said.
Zac Olumegbon from Brixton Hill, south London, was attacked at the gates of Park Campus School in nearby West Norwood last Friday.
A 16-year-old boy, who cannot be named due to his age, has been charged with his murder, along with causing grievous bodily harm to Zac's 14-year-old friend.
He will appear at Sutton Youth Court on Friday morning, said a spokesman for Scotland Yard.
Two other boys, aged 16 and 17, have already been charged and appeared at Sutton Youth Court on Wednesday.
Police and the ambulance service were called at 8.50am on Friday to Gipsy Road Gardens, where they found Zac suffering from multiple stab wounds.
He was taken to a south London hospital and confirmed dead shortly after arrival. A post-mortem examination found the cause of death was stab wounds to the chest.
Zac's companion was also taken to a south London hospital, suffering minor injuries.
More than 3,000 people joined a Facebook group called R.I.P Lil Zac. Zac was the 13th teenager to be killed in the capital this year as senior officers battle to keep a lid on violence among young people. Hailed as the first of its kind on its launch two years ago, Park Campus is a specialist school educating some of London's most troubled young people.
Two other teenagers, aged 16 and 17, have been released on bail until August, pending further inquiries.