Michael Olatunde Fadayomi, a Nigerian man has been killed in London.
The man was stabbed to death in front of his teenage son before the murderer 'walked away calmly'.
Michael Olatunde Fadayomi - known as Tunde - was killed on Thursday in the street after a fight began on a London bus and spilt out onto Willesden Street.
The victim's teenage son desperately tried to intervene as his father was repeatedly stabbed in the footage.
Emergency services were called shortly after 5pm on Thursday, but Tunde died at the scene.
A passenger on the bus who witnessed the tragedy told the Mirror that the suspect stabbed Tunde and then walked away 'without a care in the world'.
He said: "He calmly walked away. It was like nothing happened. He just walked and no one had bothered to go after him. This is a very dangerous man who needs to be taken off the streets before he strikes again."
The witness, who wished to remain anonymous, said the argument started when the suspect accused Tunde's son and his friend of preventing the bus from moving, whereas the vehicle was stationary because it was changing drivers.
"The bus had stopped outside Willesden Garage and the man just kept shouting that he needs to see his mum, and then he started accusing the boys of being the reason why the bus wasn't moving.
"I was on my phone and was thinking ', why is this grown man shouting at these boys'. The boys were trying to calm him down but then he reached into his crotch and pulled out a blade. The boys ran off the bus and one said he was going to get his dad."
The suspect had reportedly come off the bus too but went back on shortly before Tunde boarded and made his way up the stairs.
The witness said: "The dad asked the man why he had troubled his son. They started shouting at each other before the killer took out the knife again and said, 'I want to go and see my mum."
Mobile video footage showed the two men arguing on the top deck before the dad comes off the bus, followed by the suspect.
The witness continued: "They started fist fighting on the street before the man started stabbing the dad. People started screaming and after the dad fell, the knifeman stood in the road with everyone else."
Harrowing video footage shows the two fighting as Tunde is fatally stabbed.
Bystanders can be heard screaming while others try to intervene in the distressing clip circulated on social media.
The witness said he was disgusted by the actions of people who whipped out their phones after Tunde had been stabbed rather than try and help him.
He said: "I was the only one who called the police. We need to change how we use technology and use it sensibly, not stand by and watch a man dying.
"This man died protecting his son. As a father myself, I understand why he confronted his killer, and we would do the same. He did what any decent father did and he lost his life while the killer walked away without a care in the world. He needs to be found and quickly."
A teenager, thought to be Tunde's son, is seen in a video being comforted in the aftermath of the killing.