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 drug dealer has been jailed for stabbing a police officer who tried to apprehend him in a park in Portsmouth.
PC Russell Turner, 56, suffered a collapsed lung after being stabbed twice by Michael Enzanga in February.
Enzanga, 20 was found guilty of causing grievous bodily harm with intent, possession of a knife and drugs offences following a trial in August.
He was jailed for 16 years and ordered serve at least two thirds before consideration for parole.
Prosecutor Dale Sullivan said the case was made more serious because the stabbing took place near to a nursery, and because it was against a police officer.
In an emotional statement, PC Turner told the court on Wednesday he felt anger towards Enzanga for leaving him lying in his “own blood”.
“Most of all I can never forgive him for the upset, pain and emotional trauma he caused my family,” said PC Turner.
‘Thinking all sorts’
“On the day I was stabbed my wife was at home and my sergeant knocked on the door and told her what happened.
“During that half hour car journey her mind was thinking all sorts, wondering if I was going to live.”
A father-of-two, PC Turner was not able to return to work for 10 weeks and has now left Hampshire Constabulary.
During the trial jurors heard how PC Turner was stabbed during a “full-on fight” with Enzanga while investigating reports of drug dealing in Stamshaw Park.
The plain clothes officer got out his warrant card out and identified his colleague and himself as police officers when Enzanga tried to run away and the struggle broke out.
‘Hiding under tarpaulin’
His colleague PC Clare Parry broke down in tears as she described Enzanga as like a “caged animal fighting for his life”.
After the stabbing, Enzanga fled in the direction of a block of flats but was seen by members of the public and on CCTV carrying a knife before being Tasered by officers.
He was eventually found hiding under a tarpaulin in a back garden with the barbs from the Taser still lodged in his back.
Enzanga, of Ashfield Road, Tottenham, was also convicted of four charges of possessing crack cocaine and diamorphine (heroin) with intent to supply, and a charge of possessing criminal property in the form of £1,000 in cash.
A man stabbed to death at a London Underground station was an Arsenal fan on his way to a match.
Tashan Daniel, 20, was fatally wounded in an “unprovoked attack” on the platform at Hillingdon station on Tuesday shortly before 16:00 BST.
He had been heading to the Emirates Stadium to see the Gunners face Nottingham Forest in the third round of the Carabao Cup.
It is the third murder investigation on the Tube network this year.
A spokesman for the Premier League club said: “Everyone at Arsenal Football Club is shocked and deeply saddened to learn of the tragic passing of Arsenal fan Tashan Daniel.
“Our thoughts are with Tashan’s family and friends at this sad time.”
Mr Daniel, who had recently celebrated his birthday, was on the platform waiting for a Piccadilly Line train into central London when he was attacked by two men, British Transport Police (BTP) said.
Attempts were made to save Mr Daniel who was pronounced dead inside a Tube carriage.
Det Ch Insp Sam Blackburn said no arrests had been made, but both suspects left the station in the direction of Auriol Drive and a knife was recovered nearby.
“Tashan did not deserve to lose his life during this senseless attack,” he said.
“His family are completely broken by this news and we are doing everything we can to offer them support.”
Extra officers are going to be carrying out patrols in the Hillingdon area, Det Ch Insp Blackburn added.
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.”
The station was closed by Transport for London (TfL) while police searched the area.
It remained closed for the rest of Tuesday evening and reopened at 05:45 on Wednesday.
So far in 2019 more than 100 murder investigations have been launched across London by the Metropolitan Police and BTP.
A teenager has been stabbed to death in Newham, east London.
The Metropolitan Police said the man, believed to be 18, was found critically injured with stab wounds at 15:30 BST in Chadd Green.
Officers and London Ambulance Service attended. The teenager was pronounced dead an hour later.
The Met said the next of kin had been informed. A post-mortem examination and formal identification are being arranged.
An investigation is under way, but there have not yet been any arrests.