A 16-year-boy was stabbed "in the back" as he ran from gang members who were "looking for violence", a court heard.
Jaydon James, known as JJ, died in hospital shortly after being stabbed in Wood End, Coventry, in November 2018.
Frank Kenfack, 18, of no fixed abode, Bongani Ngozi, 18, of Hinckley, Leicestershire; and 20-year-old Abdi Hussein, of Coventry, deny his murder.
Prosecutor Michael Burrows told Warwick Crown Court the attack resulted from an ongoing feud between two rival gangs.
Opening the case against the three defendants, Mr Burrows said on the night of 24 November, the RB7 gang, which is based in Coventry city centre, was seeking revenge and members drove to the Wood End area looking for members of rival gang C2.
He said the trio in a black Peugeot were "armed with weapons, with knives".
"They were out looking for people to attack, looking for violence. Their motive is clearly to cause at least really serious injury, if not to kill," he said.
Mr Burrows said they spotted and chased Jaydon and two of his friends, were were also stabbed.
"They stabbed Jaydon James in the back. It's clear that he was running away from them."
"We say you can be sure that whoever stabbed him intended to kill him," he said.
The court was told Jaydon, who was cornered in a church car park in Deedmore Road, was stabbed with so much force the knife went through his body.
Mr Burrows described the attacks as a "joint enterprise" by the defendants.
Mr Ngozi of Rosemary Way, Mr Hussein, of Foleshill Road, and Mr Kenfack also all deny intent to cause grievous bodily harm.
The jury was told a feud between the RB7 and C2 gangs had resulted in previous attacks, some involving shootings.
The case continues on Monday.
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