Keelan Wilson murder: New appeal over Wolverhampton stabbing
Witnesses have been urged to ditch a "misguided sense of loyalty" by police investigating the stabbing of a 15-year-old boy.
Keelan Wilson died after a fight on Langley Road, Merry Hill, Wolverhampton, on 29 May last year.
Nine teens were arrested by West Midlands Police in connection with his murder, but no-one has been charged.
Mother Kelly Ellitts said her son was "executed in a vicious attack by gang members who boast about it online."
Issuing a fresh appeal on the one-year anniversary of his death, police said they were "determined now, as we were then, to get justice for his family."
Det Ch Inspector Chris Mallett said: "I appreciate there may have been people who didn't feel they could speak to officers at the time due to a sense of misguided loyalty.
"But this a 15-year-old boy, who had his life ahead of him, who has been taken away at the hands of a knife and we need to ensure justice prevails.
"Any piece of information, however insignificant you feel it is, could be crucial in cracking the case."
Three suspects, aged 16, 17 and 18, were arrested on suspicion of murder last month and have been released under investigation until 9 July.
Six other teenagers arrested previously have also been released under investigation.
Ms Ellitts had previously said she felt "let down" by the police investigation.
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