A 19-year-old man has been arrested after a stabbing which left a 16-year-old boy fighting for life in Ruislip, north-west London.
Police were called to the scene in Victoria Road shortly before 5pm on Thursday, where the victim was treated for stab wounds.
He was rushed to hospital where he remains in a life-threatening condition, a Met Police spokesperson said.
The boy’s family have been informed and are being supported by specialist officers.
Met Detective Inspector Tony Smith, who is leading the investigation, said: “We recognise this is a distressing incident and we have upped local foot patrols and will ensure there is a visible police presence over the weekend.
“Although we have a suspect in custody, we are working round the clock to build a picture of what happened and I would ask anyone with information to contact us immediately."
A crime scene remains in place in the area, with Victoria Road closed from the Stonefield Way junction to the Field End Road roundabout.
Police are encouraging people to avoid the area where possible to minimise congestion.
Anyone with information that could assist police, or who may have captured the assault on a doorbell or dash cam, is asked to call 101 or visit ‘X’ @MetCC and quote 5631/06Mar.
You can also provide information anonymously to the independent charity Crimestoppers on 0800 555 111.
