A 15-year-old has been charged with conspiring to murder a schoolboy who was stabbed to death in the street.
Baptista Adjei, also 15, from North Woolwich, was attacked on Stratford Broadway, east London, on 10 October.
Police have charged another 15-year-old boy with murder, GBH and two counts of possessing an offensive weapon.
The latest suspect will appear at Stratford Youth Court later, Scotland Yard said.
A man stabbed to death at a London Underground station was an Arsenal fan on his way to a match, the BBC has been told.
Tashan Daniel, 20, was was killed in an “unprovoked attack” on the platform at Hillingdon station on Tuesday.
He had been heading to the Emirates Stadium to see the Gunners face Nottingham Forest in the third round of the Carabao Cup, a source said.
It is the third murder investigation on the Tube network this year.
No arrests have been made over the attack, which Det Supt Gary Richardson described as “a shocking act of violence”.
He said the British Transport Police (BTP) investigation was in its “early stages”.
“We believe a group of young men were involved in an altercation on the platform before one of the men received a fatal stab wound,” he said.
Police and paramedics were called to the station in west London at 15:57 BST.
An air ambulance was also sent to Hillingdon, but Mr Daniel was pronounced dead at the scene.
Danielle Foster, who was driving past Hillingdon station at the time of the stabbing, said upon “hearing so many sirens, I knew something terrible had happened”.
“Lots of people were being turned away from the station as it had been closed,” she said, adding: “Then the police helicopter began circling the scene.”
Hillingdon station was closed by Transport for London (TfL) while police searched the area.
The station was closed for the rest of Tuesday evening and reopened at 05:45 this morning.
So far in 2019 more than 100 murder investigations have been launched across London by the Metropolitan Police and BTP.
A fourth teenager has been arrested on suspicion of the murder of a boy at a chicken shop in central London.
Josiph Beker, 17, was stabbed to death outside Edgware Road KFC, Westminster, at about 14:00 BST on 10 September.
A 16-year-old boy was arrested on Sunday in connection with the murder. He remains in custody.
Two 16-year-old boys were charged with murder on Saturday. An 18-year-old arrested over the murder has been bailed pending further inquiries.
Three people have been arrested on suspicion of attempted murder after a 15-year-old boy was stabbed.
The victim remains in a critical condition in hospital following the attack in Tottenham, north London, on Friday.
He was found with multiple stab wounds on Willan Road, in the Broadwater Farm estate, at around 11:15 BST.
Scotland Yard said three males were detained in connection with the incident on Friday evening.
Officers believe the boy was involved in an altercation shortly before he was stabbed, possibly by a suspect riding a bicycle.
Police would like to speak to members of the public who gave first aid to the victim at the scene.
Det Insp Paul Ridley said: “I am keen to hear from anyone who either witnessed, or has information concerning this attack.
“The victim, not yet 16 years old, sustained multiple stab wounds and is fighting for his life.
“If you know anything about the circumstances surrounding the incident or if you witnessed it, please do come forward.
“I would also appeal to the members of the public who valiantly administered crucial first aid to the victim to come forward to my investigation team.”
Anyone with information is asked to contact police on 101.
A man has died after a triple stabbing in north London.
Officers were called to Welbeck Road in Barnet at 22:50 BST on Tuesday after reports of a fight.
Scotland Yard said three people had been taken to hospital and a man in his 30s was pronounced dead – the fifth killing in the capital in six days.
Two other injured men, one in his 20s and one in his 30s, have been discharged from hospital. The Met has launched a murder investigation.
The fatal stabbing comes after a man in his 40s was knifed to death in Whalebone Lane, Stratford, in the early hours of Monday.
That followed three homicides in the space of 24 hours, including two teenagers who were fatally attacked on Friday.
Cheyon Evans, 18, was found stabbed on Deeside Road in Wandsworth, south-west London, at 16:42 BST, and died at the scene.
Eniola Aluko, 19, from Thamesmead, south-east London, was shot dead in Hartville Road, Plumstead, shortly before 17:00.
On Saturday, Gleb Stanislavovitch Zhebrovsky, 30, was stabbed to death in a field in Alton Street, in Tower Hamlets, east London, just before 14:00.
The Met Police said it has stepped up patrols in certain hotspots.
Mohamed Nadir Dafallah, 18, from Wandsworth, and a 17-year-old, who cannot be named for legal reasons, have been charged with Mr Evans’ murder.
They are due to appear at the Old Bailey on Wednesday.
A man, believed to be in his 40s, has been stabbed to death in east London.
The man was found collapsed in Whalebone Lane, near West Ham Lane, Stratford, at 00:40 BST and was later pronounced dead at the scene.
His death was the fourth killing in London in three days – there have been two other stabbings, and a shooting.
The victim’s next of kin have been informed. A post-mortem examination has yet to take place. No arrests have been yet made.
‘More patrols needed’
Local resident Rema Klayton said she had been left “shaken”.
“The Met is aware of what is happening in Newham, namely the number of knife crimes. It would be nice to see the police doing more patrols in the area.
“The area is changing for the worst, not for the better.
“The crime rate is very high and we need help. People are looking to move out of Stratford right now.”
A crime scene remains in place and there are road closures on West Ham Lane between Widdin Street and Paul Street. Stratford Park also remains closed.
A section 60 order, which allows police to stop and search people, has been put in place for the whole of Newham borough until 18:00.
Mayor Sadiq Kahn said the incidents were “heartbreaking”.
“You can’t sugar-coat that the last four days have been awful,” he said.
“The families will never be the same again”.
An 18-year-old man was stabbed to death on Friday afternoon in Wandsworth, south London. Two teenagers have been charged with murder and another man in his 20s was arrested on suspicion of murder on Monday.
Minutes later 19-year-old Eniola Aluko was shot dead in Plumstead, south-east London. Five people were arrested.
On Saturday, a man in his 30s died after he was stabbed in Tower Hamlets.
The deaths take the total number of homicides in London in 2019 to 57. This time last year there had been 77 homicides, 48 of which were stabbings.