CCTV footage has captured the moment a 'murdered' ice cream seller was seen arguing intensely just seconds before he was stabbed to death.
Police officers responded to reports of an altercation in Monks Park in Wembley at 6.10pm on Tuesday, where they found victim Shazad Khan, 41.
He was sadly pronounced dead shortly after paramedics arrived at 6.15pm.
His family have been informed and a murder investigation has been launched, the Met said.
A 26-year-old man was arrested on suspicion of murder in the early hours of Wednesday, while a 31-year-old woman was also arrested at the scene for conspiracy to murder, the force said. Both remain in custody.
Witnesses told yesterday they watched on in horror as Mr Khan was stabbed eight times.
New video footage has shows Mr Khan, dressed in a grey tracksuit with a black apron, stood outside the cab of his van speaking with another man in the seconds before he was killed.
The pair were seen animatedly conversing before Mr Khan turned to take off his apron.
The second man, who was wearing a hooded grey tracksuit and blue sliders, can be seen animatedly gesturing at Mr Khan, appearing to jab him in the chest.
The ice-cream seller then turns around and walks a few steps away while seeming to reach behind him to untie his apron.
According to the Metro, he was stabbed five seconds after the footage ends.
Yesterday local residents told how Mr Khan was well known in the area for selling ice creams in a van.
He usually had a large teddy bear riding in the van's passenger seat and was so well liked for his cheerful demeanour that he was nicknamed 'Mr Smiley'.
Asim Mahmood Butt, 39, who lives in nearby Tokyngton Avenue, said he was childhood friends with the victim.
Speaking at the scene, he said: 'I got a call from one of my cousins. This guy, we know him - he's a famous ice cream guy. He got stabbed yesterday.
'I came here and his body was still here, and police had cordoned off the area.
'We don't know the reason why, but all that we know is that a guy with a grey hoodie stabbed him eight times. That's what I've been told.
'I know his brothers as well - they're all local. We all used to play cricket and football here in Monks Park. He started (selling) ice cream about a year ago.'
Mr Butt said the victim was married and had a young daughter.
The victim's ice cream van, which had been parked on the road at the time of the incident, was well known locally for its large teddy bear, the witness added.
A second witness, who did not want to be named, said the ice cream van was towed away from the scene in the early hours of Wednesday morning.
A blue forensics tent and a number of Met officers could be seen inside a police cordon in Monks Park on Wednesday.
Removal vehicles also took away a separate white van and blue car.
Detective Chief Superintendent Luke Williams, local policing commander for north-west London, said: 'Our thoughts remain with Shazad's family and friends at this unimaginably difficult time.
'This incident will rightly cause concern across the community, but intelligence at this stage leads us to believe there is no wider threat to the public.
'Detectives are conducting a thorough and fast-paced investigation, and locals can expect to see an uptick in police presence in the area.
'Anyone with any information - particularly dashcam or doorbell footage from the time of the incident - is urged to speak to us as a matter of urgency.'