A gang member will serve a minimum of 27 years behind bars after murdering a rival in an Edmonton car park.
Natneal Tesfay gunned down 19-year-old Mohammad Hussein with a shotgun as he walked through a car park on April 1, 2013.
A bitter on-going dispute between an Enfield and Edmonton gang is thought to be the reason for the shooting.
On the evening of April 1, members of the Edmonton group, including Tesfay, gathered in Bounces Road, in Edmonton.
A dark Vauxhall Corsa drove past, in which it is thought members of the Enfield gang were riding, and Tesfay and others gave chase.
Tesfay then left and returned later with a bag containing a sawn-off shotgun and ammunition.
Ten minutes later, a black BMW arrived and the victim, a member of the Enfield gang, got out and began walking towards the Best Kebab shop, in Bounces Road.
He was followed by members of the Edmonton gang before Tesfay calmly put down the bag and fired at Mr Hussein, who was unarmed, before chasing him down and shooting him again.
Mr Hussein had been hit in the chest and collapsed in an alleyway between Bounces Road and the car park. He was found by a male member of the public who called an ambulance. A passing nurse also tried to help but Mohammed died at the scene.
The prosecution at Kingston Crown court said that Tesfay had fired the gun "like something out of the old western movies".
Tesfay was seen on CCTV to calmly put down his bag, take out the shotgun and fire at Mohammed, who was unarmed. He then chased after him and shot again.
The male from the BMW ran across and pointed his gun at Tesfay's group but, for whatever reason, it did not fire and he got back into the vehicle which drove off.
Tesfay, of Park Road, Edmonton, was arrested on Wednesday, April 3, last year and was subsequently charged.
As well as the life sentence, Tesfay also received a ten year sentence for possession of a shotgun with intent to endanger life which will run concurrently.
Investigating officer detective chief inspector John Sandlin, said: "This case is a terrifying example of how gangs ruin lives.
"Rivalry between two groups led to the death of Mohammed, gunned down in the street. Tesfay was prepared for violence that night and when he went to collect a shotgun there could be no doubt he was ready to use it as he saw fit."