A man has been arrested on suspicion of murder following the shooting in Kilburn on Thursday (December 8) .
It comes as police name the 21-year-old victim as Yasir Beshira.
A post mortem carried out on Saturday (December 10) at Whittington Hospital Mortuary has also revealed he died from a single gunshot wound to the abdomen.
The 22-year-old murder suspect was arrested on Saturday and remains in custody at a north London police station.
The Homicide and Major Crime Command (HMCC) launched their murder investigation after police were called at 5.20pm to reports of man collapsed in Netherwood Street.
Officers and paramedics found members of the public helping Mr Beshira but he was pronounced dead at 6.20pm.
At this stage police believe the victim was approached by a lone male suspect in Palmerston Road and shot. He then staggered to Netherwood Street where he collapsed.
The suspect made off in the direction of Palmerston Road towards the Webheath Estate.
Witnesses describe the gunman as being a slim white male, wearing a dark hooded top with the hood up and he had his lower face covered. He was wearing jeans.
Despite the arrest Detective Chief Inspector Andy Partridge, leading the HMCC investigation , continued his appeal for information.
He said: “I believe this person was loitering in and around Palmerston Road and the Webheath Estate prior to the attack.
“Following the incident he fled along Palmerston Road and into the Webheath Estate. It is my view that this suspect would have stood out hanging around at this location and certainly when he fled through the estate following the attack.
“If anyone saw a person fitting this description either before or after the attack, I am appealing for them to come forward to assist the investigation.”
He said there had been a positive response from the rocked community , with a number of witnesses coming forward. He also said there was an extra police presence in the area and that officers are carrying out reassurance patrols.
He added: “We know the area was extremely busy at the time of the shooting. I am convinced that other members of the public have either seen the incident itself, or have seen the suspect arrive at the scene or flee after the shooting.”
Anyone who can help police can call the HMCC incident room on 020 8358 0300 or the police non-emergency line on 101.
The Crimestoppers number is 0800 555 111.
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