A man was stabbed to death in a fight outside a block of east London flats in a “particularly vicious attack”.
The 19-year-old was found by police responding to reports of a disturbance outside Owen Waters House, in Fullwell Avenue, Ilford, on Tuesday night.
The victim died at the scene and his next of kin have been informed.
No arrests have been made but the Met said “the possibility that the murder is gang-related is a very strong line of inquiry”.
Police are establishing if the stabbing is linked to a fire at some nearby garages where a car was found burnt out.
The Met said fire crews had been called to the blaze at about 22:20 GMT while traces of blood had also been found around the vehicle.
Det Ch Insp Chris Soole described the killing as a “particularly vicious attack” and appealed for witnesses.
A Section 60 Order – giving police stop-and-search powers – was put in place for the whole of the Redbridge borough until 06:30.
There have been five murder investigations in the borough in 2019 – three of which have been as a result of fatal stabbings.
Homicides in London since 2008
Annual homicides in the Met Police area
So far this year, almost 130 murder investigations have been launched in the capital.
Three investigations have been carried out by British Transport Police and 124 have been investigated by the Met.
At the scene – Greg McKenzie, BBC London
A forensic tent is outside the tower block marking the spot where the teenager died.
Residents have been telling me about rising tensions in the last few weeks. The block – just off a main road in Ilford – is known as a meeting point for drug dealers and people said the issue is “rampant”.
They have also described a lot of “youth disturbance and violence” in the area and expressed their fear, anger and shock.
Officers have been coming in and out of the flats and they are trying to work out whether a burnt-out car is linked to the fatal stabbing.
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 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.
Two teenagers have been charged with murdering another boy who was stabbed in central London.
The two 16-year-olds have been charged with attacking Josiph Beker, 17.
The Met Police said officers were called to Edgware Road, near to the junction of Church Street, at 13:54 BST on Tuesday.
There officers found Josiph, who was also known as Yousef, had been stabbed in the chest. He was taken to hospital but died at about 19:30 BST.
The 16-year-olds will appear before Highbury Corner Magistrates Court.
An 18-year-old was also arrested in connection with Josif’s murder but he has been bailed pending further inquiries.
A teenage boy has been stabbed to death in east London.
Police officers were called to Byford Close in Stratford at 18:45 BST on Tuesday following a report of a fight, the Met Police said.
No arrests have been made but the death is being treated as murder. It is the 93rd homicide in the capital this year.
A section 60 order, which allows police to stop and search people, has been put in place for the whole of Newham borough until 12:30.
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 16-year-old boy has been stabbed to death in north-west London.
Police officers and the London Ambulance Service were called to Munster Square in Camden at about 23:10 BST on Monday.
Scotland Yard said the victim was pronounced dead at the scene and no arrests have been made.
A murder investigation has been launched and a crime scene remains in place. The Met has urged witnesses to come forward.
A large police cordon stretching across a number of roads was in place on Tuesday morning.
A man who was stabbed to death inside a west London shop as he tried to hide following a fight has been named by police.
Yusuf Mohamed died at the scene after he was attacked in Uxbridge Road, Shepherd’s Bush, on Wednesday night.
Witnesses said the 18-year-old went into the store “for cover” but was followed and stabbed.
No arrests have been made but police said they were looking “two males, possibly in their teens”.
The pair were seen on CCTV running away from the area in the direction of Wormholt Park.
A post-mortem examination found Mr Mohamed, who was from the Hammersmith area, died from a stab wound.
Passers-by have been laying flowers outside the shop in tribute to the 18-year-old.