A fifth teenager has been charged with the murder of Shakilus Townsend who was stabbed to death in south London last week, police said on Friday.
Detectives said the 16-year-old boy was due to appear before Sutton Magistrates Court later.
Townsend, 16, was found with a stab wound in the entrance to a block of flats in Thornton Heath last Thursday. He died in hospital the same night.
On Thursday four teenagers, including one girl, appeared in court charged with his murder. Tyrell Ellis, 18, two other young men aged 16 and 17, and a 15-year-old girl were remanded in custody.
A 22-year-old man has been released on police bail until a date in August pending further investigations.
Townsend was one of 19 teenagers to die violently in the capital this year.
The Metropolitan Police have said knife crime was now the force's top issue.
Officers say they have searched 27,000 people, arrested more than 1,200 and seized 500 knives in London during a six-week crackdown. A 75-strong team has also been set up to target those carrying weapons.
"This reflects that tackling knife crime is the number one priority for the Met at this time," said Deputy Commissioner Paul Stephenson.
News
Russia and Ukraine agree to temporary Orthodox Easter truce
In the Orthodox calendar, Easter falls one week after the date celebrated in western Europe.
Bishop urges people of Britain to stand up for Christian truth
It follows an earlier open letter addressed to King Charles, calling upon him to defend Christianity in line with his titles of Supreme Governor of the Church of England and "Defender of the Faith".
Fundraising Regulator reminds churches that collections are subject to code of practice
Churches can breach the code even when acting in good faith.
Religion is often left unspoken in the workplace despite widespread faith identity, research finds
Fifteen per cent of UK employees with a faith say they have experienced religious discrimination in the workplace.