An innocent 13-year-old boy was shot in the head after being caught up in the cross-fire of a suspected drug deal gone wrong during a Bank Holiday weekend of violence in London.The youngster had been attending a wedding with his parents in Wealdstone and was walking along the High Road on Sunday afternoon when he was hit by a stray shotgun pellet.Police investigating the shooting – which was one of a spate of gun and knife incidents over the weekend – described it as a “callous, reckless and brazen act”.A 15-year-old youth, who is thought to have been the target in the attack was also wounded in the head, but was not thought to be in a life threatening condition.In response to the weekend of violence, the Metropolitan Police has increased patrols – including of armed officers – in hotspots across the capital. An item of clothing lies on the pavement at the junction of Palmerston Road and the High Street, in Wealdstone A hooded jumper lies on the pavement next to an evidence marker near the scene of the shootingCredit:Jonathan Brady /PA Police close to Palmerston Road and the A409, following two shootings Rhyhiem Ainsworth Barton was shot dead in south London Man, 22, shot and wounded by moped riderOn Sunday evening a 22-year-old man was shot and wounded in New Cross in south east London.Police were flagged down by a member of the public in New Cross Road, after discovering a man suffering from a gunshot wound. It takes the number of people murdered in the capital since the start of the year to 62.Rhyiem’s  mother, Pretana Morgan, 38, called for an end to the violence.She said: “Let my son be the last and be an example to everyone. Just let it stop. What must be, must be.”Video: Victim’s mother calls for end to bloodshed Scotland Yard increases patrols across LondonIn response to the violence the Met has increased patrols in hotspots across the capital.Detective Chief Superintendent Simon Messenger said: “The violence used has rightly caused concern and we are doing all we can to address this.”Over the Bank Holiday weekend, additional officers are on the streets across the capital, working hard to keep London safe.”They are using highly visible local patrols supported by armed response, traffic motorcycles, dog units, and air support – alongside plain clothes intelligence-led operations.” He added: “Violence has no place on our streets.”How violent crime soared in 12 months Locals in the busy Wealdstone High Street who rushed to the scene helped treat the 13-year-old until police and paramedics arrived.One local resident said he had heard the shooting had been the result of a drug deal gone wrong.He added: “The 13-year-old was attending a wedding and was just in the wrong place at the wrong time.” Shootings and stabbings elsewhere in UKAnother shooting took place in Clayton, Greater Manchester Police said.A man in his late teens was with his friends when he was shot in the leg shortly before 2.45pm on Monday.He was taken to hospital for treatment of serious injuries.Elsewhere, in the country a 20-year-old man died after being stabbed to death in Merseyside.Fatah Warsame, from Cardiff, was taken to hospital in the early hours of Sunday morning but was pronounced dead a short time later.In Manchester police were also investigating a shooting in which a teenager was wounded in the leg. Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily  Front Page newsletter and new  audio briefings. A police cordon close to the scene of the shooting in Wealdstone on SundayCredit:Jonathan Brady /PA The injured man was taken by ambulance to a central London hospital where his condition is not thought to be life threatening.A Scotland Yard spokesman said: “At this early stage, it is believed that two male suspects riding one moped shot the victim, a pedestrian, at Besson Street. Officers retain an open mind as to any motive. There has been no arrest and enquiries continue.”Resident stabbed in dispute with motoristA short time later a 43-year-old man was stabbed in Perivale to the west of the city, following a dispute with a motorist on a quiet residential street.Elsewhere, three men aged 22, 27 and 17 were left with life changing injuries after being targeted in an acid attack in the early hours of Monday in Hackney, east London.’Delivery driver’ shot in south east LondonIn a fourth Bank Holiday weekend shooting in the capital, a 30-year-old man – who may have been working as a delivery driver – was gunned down.Police were called at 4.50pm on Monday to a shooting in John Williams Close, in New Cross, south east London, Scotland Yard said.The victim was treated at the scene before being taken to hospital. His condition is not believed to be life-threatening. Detective Chief Superintendent Simon Rose, Harrow Borough Commander said: “It would appear that the first victim was approached by two male suspects, one in possession of a shotgun – and shots were fired injuring him and an entirely innocent member of the public. “This was a callous, reckless and brazen act, without any thought by those responsible for the fact that there were families with children and people in the high street enjoying their weekend. This was quite simply, appalling.”The incident was one of four shootings across London during the Bank Holiday weekend, which left one man dead and at least four injured.Rapper gunned down in drive-by shootingOn Saturday, 17-year-old Rhyiem Ainsworth Barton, a rapper and aspiring architect, was gunned down near his home in Kennington, south London, in what is thought to have been a drive-by shooting. Rhyhiem Ainsworth Barton was shot dead in south LondonCredit:AFP/Getty