Five men were jailed for life over the murder 16-year-old Hani Abou El Kheir, who was stabbed to death in Pimlico last January.
The teenager was assaulted with weapons including swords, a meat cleaver, knives and a Taser stun gun.
Hani Abou El Kheir was stabbed more than 20 times while walking through an estate in Pimlico.
The "casual" acceptance of knives led to the death of 16-year-old Hani Hicham Abou El Kheir, a Metropolitan Police officer said after five men were sentenced to life in prison.
After sentencing, Detective Chief Inspector Neil Attewell said:
Hani had been out with friends when he was chased and set upon en masse.
The frenzied attack through the streets of Pimlico left at least two of the gang members with injuries, which gives a clear indication of the ferocity at which they attacked Hani. Sadly Hani stood very little chance of being able to escape.
The mother of a teenager stabbed to death in Pimlico last year has described Hani El Kheir as a "gentle and loving giant".
Speaking outside the Old Bailey after five men were sentenced to life in prison for his death, Parish Priest Canon Pat Browne read a statement on behalf of Hani's mother Pauline.
CCTV footage has been released of the moments after a teenager was stabbed to death in Pimlico in a frenzied attack. Five men were sentenced to life in prison today over the murder of Hani Hicham Abou El Kheir.
The jury heard how the gang carried an array of weapons and with their faces covered had caught up with the trio and began to give chase pursuing them through an alleyway.
The gang finally caught up with Hani in Lupus Street and he was repeatedly stabbed in a frenzied ambush. The attackers are then seen scattering off in a number of directions.
Five men who stabbed a teenage boy to death in a frenzied attack have been sentenced to total of 131 year's imprisonment for the murder of Hani Hicham Abou El Kheir.
Ahmed Mikhaimar, Arber Barbatovci, Tarquai Joseph, and another 20-year-old man, who cannot be named for legal reasons, were jailed for 26 years.
Craig Boyce was sentenced to life with a minimum of 27 years.
The judge has described the murder of Hani Hicham Abou El Kheir as "savage and calculated", after he was stabbed to death in Pimlico last January.
Four of men convicted of the murder of Hani Hicham Abou El Kheir have been given a minimum life sentence of 26 years. A fifth man was given 27 years after the teenager was stabbed to death in Pimlico last January.
Judge agrees last moments of Hani El Kheir as he was confronted with men with knives and swords "utterly, utterly terrifying" @itvlondon
5 men due to be sentenced for murder of 16 year old Hani Hicham Abou El Kheir. Teenager was stabbed 20 times in Pimlico. @itvlondon