Six teenagers are facing sentences of between 11 and 16 years in detention after stabbing an 18-year-old boy to death metres away from his front door.
Lyndon Davis died after an attack on March 14 last year, by a group who chased him down and stabbed him in an alley close to his home in Nash Road, Romford.
Paramedics found him bleeding heavily in the alley from five large knife wounds, and despite three attempts to revive him, Lyndon died in hospital a few hours later.
Prosecutor Brian ONeill, QC, told the court the six youths, as well as two other suspects who have not been identified, targeted Lyndon due to his involvement with a rival gang.
Five of the boys had been involved with the OC gang, with the exception of then-14-year-old Ali, who was not a member.
Mr ONeill said: This was a gang of eight who went out that night. This was a deliberate and planned ride into enemy territory. They did not find themselves in Marks Gate that night by accident.
It is plainly a gang crime and that has always been our case. These offences were committed in the context of gang criminality and involved the use of knives.
Mr ONeill said that five knives were seen in the hands of members of the group, who were all charged with joint possession of offensive weapons.
Jordan Worrie, 18, Connor Corcoran, 18, his 17-year-old brother Michael Corcoran, and Tyler Faubel, 18, all from Hainault, were convicted of murder by a jury in July.
Jordan Muingilu, 18, from Wanstead, and Ali Ali, 16, from Ilford, were also convicted.
The six youths, who were all under 18 at the time of the murder, were given life sentences with minimum terms of between 11 and 16 years in detention at Woolwich Crown Court on Monday.
The identities of four of the teenagers were withheld before sentence due to their ages, but all six can now be identified after a media application to name Ali and Michael Corcoran.
Muingilu and Connor Corcoran turned 18 after their convictions.
Woolwich Crown Court heard Faubel had been caught with large Rambo-style knives and that the knives used in the fatal attack were large and designed to specifically cause damage.
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Mr ONeill added: Such a weapon had no lawful or legitimate purpose.
After the group spotted Lyndon as he left a bus close to his home, the group chased him, and Worrie, Michael Corcoran and Faubel entered the alley with a fourth male.
The rest of the group stayed across the road during the attack, as an unidentified male waited in a getaway car while the violence took place.
However, all six were convicted and sentenced for murder, as the three who stayed away gave support and encouragement to the brutal attack.