A man has been arrested on suspicion of murder following a shooting which police say was a case of mistaken identity.
The victim, Oliver Tetlow, 27, was hit several times by a shooter who jumped out of a car in Harlesden, north west London, on Wednesday night.
The Metropolitan Police said a 29-year-old man was arrested at around 11.50pm on Friday in the Shepherd's Bush area on suspicion of murder.
An 18-year-old man was arrested in Harlesden at around 4pm on suspicion of robbery, and both men remain in custody.
Detectives are considering the possibility of the incident being gang-related but do not think the victim was the intended target.
Police and paramedics rushed to the shooting at the junction of Church Street and Conley Road shortly before 10pm on Wednesday.
They found a man in his late 20s with gunshot injuries, and he was pronounced dead at the scene.
Although officers await formal identification, they are satisfied that the deceased is Mr Tetlow from the Harlesden area.
A post-mortem examination gave cause of death as gunshot wounds.
Detective Chief Inspector Mark Lawson of the homicide and major crime command has appealed to anyone who may have images or footage of the shooting to contact the incident room or Crimestoppers.
Mr Lawson said: "The investigation to identify and arrest those responsible for this senseless murder is moving at a very fast pace, and I would like to thank everyone who has so far come forward and spoken to the police.
"At this early stage in the investigation, we are exploring that the shooting was gang related - however I am satisfied that the victim was not the intended target and this was a tragic case of mistaken identity.
"Early indications are that shots were fired from an automatic weapon, although a firearm has not been recovered so we cannot speculate on the exact type.
"We do know that the victim was shot by a male who got out of a dark coloured vehicle. After the shooting, this vehicle then travelled south along Church Street towards Harlesden Town Centre. I would like to hear from anyone who saw a vehicle which perhaps caught their attention.
"We are aware of information about the murder which is circulating via social media, and I would appeal to anyone who has information which could assist the investigation to contact police."
Mr Lawson said previously: ''What we can say about our victim is that he is not involved in gang violence, he is not a gang member, he is not linked to any gangs in London, and at this moment in time we are confident that he was an innocent victim.
''The family are absolutely devastated that their son has been caught up in what may be gang-related violence. They are shocked by his death.''
Anyone who witnessed the incident or has any information is asked to contact police on 020 8358 0200 or Crimestoppers anonymously on 0800 555 111.