A man has been arrested on suspicion of murder after a fatal stabbing in Willesden, Brent.
Police were called by London Ambulance Service at 17:11hrs on Thursday, 29 April to a report of a man suffering from stab wounds on High Road, NW10. Officers attended.
Despite the best efforts of the emergency services, the victim, aged 40, was pronounced dead at the scene shortly afterwards. His next of kin are aware.
Formal identification awaits. A post-mortem examination will be scheduled in due course.
A 42-year-old man was arrested following the incident at his home address in Willesden. He remains in custody. Police are not searching for anyone else in connection with this incident.
A crime scene remains in place and the public can expect to see an increased police presence in the area.
While enquiries continue, the incident is being treated as isolated and is not thought to be gang-related. The victim and suspect are not thought to have been known to each other.
Detectives from Specialist Crime are leading the investigation, led by DCI Claire Hine.
She said: "Foremost in our thoughts are the victim and his family, who are coming to terms with his very sudden and violent loss. My specialist officers are providing them with support at this very sad time.
"At this early stage in our investigation we believe the incident started on a Route 260 bus. It continued out onto the High Road and into a fast food shop in front of a number of horrified onlookers in the street, and on the bus.
"I know there are videos circulating on social media that feature some incredibly distressing images and I ask that people please refrain from sharing these to avoid causing the victim's family any more trauma.
"We've spoken to a number of people who have told us what they saw, but there are others who have yet to make contact. I would ask those witnesses to call us, so that we can fully establish the chain of events that has led to a man losing his life in such a horrific way.
"I'd also like to acknowledge that this incident would no doubt have caused incredible panic and alarm to the people who saw it. There are resources available via Victim Support (https://www.victimsupport.org.uk) that can help you if you need to speak to someone."
Anyone with information is asked to call 101 or tweet @MetCC and quote CAD 5109/29Apr. Alternatively, contact the independent charity Crimestoppers on 0800 555 111.
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