A man has been arrested on suspicion of murder after a 40-year-old man was stabbed to death in Willesden High Road as passers-by watched on in horror.

The incident at about 5pm yesterday (April 29) is thought to have started on a Route 260 bus.

According to DCI Claire Hine from specialist crime, who is leading the investigation, it continued out onto the High Road in front of "horrified onlookers", then into a fast food shop.

Despite the best efforts of the emergency services, the victim was pronounced dead at the scene shortly after the arrival of emergency services.

A 42-year-old man who was arrested at his home in Willesden yesterday remains in custody.

The incident is being treated as "isolated" by police, and is not thought to be gang-related.

Police are not searching for anyone else in connection with the incident.

DCI Hine 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."

She added: "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."

Work is ongoing to formally identify the victim, and police are in the process of locating and informing his next of kin.

A crime scene was in place overnight and the public can expect to see an increased police presence in the area.

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.

Any witnesses who need support, can contact victim support at victimsupport.org.uk.