Four people have died in suspected murders in four days in London.
A weekend of violence saw police pelted with missiles by hostile crowds near Westfield shopping centre in Stratford, east London.
A female officer also had her head repeatedly smashed against a wall as she tried to arrest a 14-year-old boy in Streatham, south-west London.
The latest homicide victim, a man in his 40s, was stabbed to death in Whalebone Lane, Stratford, in the early hours of Monday.
This followed three homicides in the space of 24 hours, including two teenagers who were killed at teatime on Friday.
An 18-year-old, named in reports as Cheyon Evans, was found stabbed on Deeside Road in Wandsworth, south-west London, at 4.42pm, and died at the scene.
Two people, a 17-year-old from Merton, who cannot be named for legal reasons, and Mohammed Nadir Dafallah, 18, from Wandsworth, have been charged with murder and will appear in court on Monday.
In the second killing, Eniola Aluko, 19, from Thamesmead, south-east London, was shot dead in Hartville Road, Plumstead, shortly before 5pm.
On Saturday a man in his 30s was stabbed to death in a field next to a nursery and a mosque in Alton Street, in Tower Hamlets, east London, just before 2pm.
As well as the violent deaths, another victim, 45, was left in a critical condition when he was stabbed in Enfield at about 3.30pm on Saturday.
The Metropolitan Police said it had boosted activity by its Violent Crime Taskforce in certain hotspots.
A section 60 order, that allows officers to search anyone to stop violence occurring, was also put in place for the whole borough of Newham until 6pm on Monday.
Newham was the scene of the latest killing as well as unrest when hostile crowds pelted police with bottles and missiles at Stratford bus station near Westfield shopping centre on Sunday.
A Met Police spokesman said about 100 people had turned on officers who were called to deal with a robbery.
Three people were arrested, two on suspicion of possession of an offensive weapon and one who is accused of robbery.
The Violent Crime Taskforce said one suspect had been found with a hunting knife.
Last night U3.2 responded to urgent assistance in Stratford @MPSNewham after officers came under attack. 1 male youth attempted to make off, was subsequently detained, searched & found in possession of this hunting knife. #TSG#LethalWeapon#LivesNotKnives ^LM pic.twitter.com/SOaSGRTryU
— MetTaskforce (@MetTaskforce) June 16, 2019
The latest string of homicides has renewed concerns about violent crime, although so far this year there have been 57 violent deaths in the capital, compared with 78 by the same date last year.
The monthly homicide rate peaked at 18 in February and March in London in 2018, compared with a high of 15 in March this year.
US President Donald Trump called London Mayor Sadiq Khan a “disaster” over the violence.
Retweeting a post by right-wing commentator Katie Hopkins about the killings, the president said the capital needed a new mayor “ASAP”.
The original post by Hopkins called the capital “Stab-City” and “Khan’s Londonistan” alongside two screenshots of BBC News articles detailing the violence.
A City Hall spokesman said Mr Khan was focusing on supporting communities and he was “not going to waste his time” responding to the president’s tweet.
He promoted a new anti-knife crime video on Twitter on Monday, as part of the London Needs You Alive campaign.