Summing up is continuing in trial of four defendants accused of stabbing of the teenager, who later died from his injuries.
Brian Sasa, Tyrique King, Zenay Pennant-Phillips and Nehemie Tampwo, all 19, are accused of murdering the youth in Wolverhampton.
Keelan, 15, suffered fatal knife wounds yards from his home in Merry Hill, Wolverhampton, on May 29, 2018 as he got into a taxi with a friend.
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In summing up, Judge Michael Chambers QC told the jury that there had been rising tensions between rival “postcode” gangs in the city known as V2 and V3 – denoting ‘WV2’ and ‘WV3’.
The court heard an officer based with the West Midlands Police’s Organised Crime Gang Unit had given evidence about gang culture in the area and that a spate of incidents had occurred between the groups.
The judge said: “There was tensions between each gang.
“They were involved in the supply of drugs and firearms.
“They were involved in so-called County Lines activities relating to the supply of drugs on other areas.”
He said the officer’s evidence was that such gangs were characterised by so-called drill music videos featuring weapons and street violence.
Keelan had been friends with Tampwo and both initially had links with him in V3 before apparently switching to V2. Judge Chambers said mutual friend of the pair had given evidence that Keelan was no longer with Tampwo’s and Sasa’s group, and that Keelan had revealed he visited Telford to be a “drug sitter” to get money.
The victim was stabbed more than 40 times in the attack, which lasted around 20 seconds. A companion who was with him in the taxi at the time was unhurt. The taxi driver also suffered minor injuries to his hands after one of the car windows was broken during the incident.
Sasa, of Long Ley, Heath Town; Tampwo, from Milton Keynes; King, of Chelwood Gardens, Bilston; and Pennant-Phillips, whose address cannot be published for legal reasons, all deny murder.
The trial continues at Wolverhampton Crown Court.