- Video report by ITV News Correspondent Neil Connery
The family of a teenager stabbed to death on a bloody weekend of violence in London have remembered the "happy" 18 year old and made an appeal to politicians to curb knife crime.
The sister and aunt of Cheyon Evans supported each other as they paid tribute at Deeside Road in Wandsworth, south-west London - the place their loved one was found stabbed.
"Before he left out they said he was singing in the bathroom - that's the last memory that we have of him - singing in the bathroom, he was very happy," said aunt Maxine Grant.
She passed on a plea from Cheyon's mother, who said "she wished that their was some way that Sadiq Khan, the government, can help these children because this knife crime has been going on for years".
She added: "It's still happening today and it's getting worse."
The appeal came as two people – a 17-year-old from Merton, who cannot be named for legal reasons, and Mohammed Nadir Dafallah, 18, from Wandsworth – were charged with murder and appeared in Wimbledon Magistrates' Court.
Dafallah and the 17 year-old were ordered to next appear in custody at the Old Bailey on Wednesday.
A 20-year-old man was also arrested on Monday on suspicion of murder and has been taken to a west London police station for questioning.
Four other people – aged between 16 and 19 years old – have been released under investigation.
It came as a 17-year-old boy became the latest victim of London's violent crime epidemic.
Met Police say the boy was shot in an incident in Tulse Hill, south London shortly before 10pm on Sunday.
He attended hospital, said police, where he remains in a critical condition.
The news comes as officers continue to investigate four deaths over the weekend in London.
The latest killing involves a 42-year-old man found collapsed and suffering stab wounds in Whalebone Lane, near West Ham Lane, in Stratford on Monday morning.
A murder investigation has been launched.
Scotland Yard said officers were called by paramedics at about 12.40am.
The man was pronounced dead at the scene about 20 minutes later - making it four killings in just 56 hours.
No arrests have been made and inquiries are continuing in relation to the Stratford stabbing, with a post-mortem examination scheduled to take place in due course.
Scotland Yard said a section 60 order – which allows police to stop and search people – had been put in place for the whole of the borough of Newham until 6pm on Monday.
The stabbing follows the deaths of two teenagers who were killed in different parts of London within minutes of each other on Friday.
The 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.
Detective Chief Inspector Larry Smith is leading the Stratford investigation. He said: “While we continue to work to piece together the events that sadly led to a man losing his life, I would appeal to anyone who was in the vicinity of Whalebone Lane from around 12.30am to contact police.
"Were you there? Did you see anything suspicious? Your information could prove vital to our enquiries.”
Officers believe they know the victim's identity and his next-of-kin have been informed.
In a separate incident, police were called to Hartville Road in Plumstead at 4.54pm to reports of a shooting.
The victim, Eniola Aluko, 19, from Thamesmead, south-east London, was found with critical injuries and died at the scene a short while later.
An 18-year-old man was arrested on suspicion of murder on Saturday, while three male teenagers and a 17-year-old girl who were arrested on suspicion of murder on Friday have since been bailed pending further inquiries.
On Saturday afternoon, police officers and London Ambulance Service attended reports of an injured man at Alton Street in Tower Hamlets, east London, just before 2pm.
The man, in his 30s, had been stabbed and was pronounced dead at the scene – a field next to a children’s nursery and a mosque – some 40 minutes later.
Officers arrested a 33-year-old man on suspicion of murder in Victoria shortly before midnight on Saturday and a 28-year-old man was arrested on suspicion of murder in Croydon, south London, on Sunday.
DCI Simon Stancombe of the Met's Homicide and Major Crime Command has made a fresh appeal for information on this incident.
He said: "Despite the two arrests that we have made this weekend, I am keen to hear from anyone who saw two males fleeing the scene on Alton Street where one ran toward the Docklands Light Railway at Langdon Park and the other ran in the opposite direction toward Giraud Street.
"I am convinced that a number of people witnessed the incident itself or the immediate aftermath and may have filmed it on their phones. I urge those people to come forward and speak to us or provide their footage."
- Why Donald Trump took aim at Sadiq Khan
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.