Detectives suspect Ishmael Farquharson is involved in the death of the teenager in Nursery Road, Lozells, last summer.
Sekou was discovered seriously injured on 12 July and despite the best efforts of officers and paramedics, nothing could be done to save him.
An 18-year-old man – and a 16-year-old male have already been charged with murder. They’re currently remanded in custody.
Anyone with information can get in touch by calling 101 quoting log 3492 of 12/7/22.
Alternatively, you can call Crimestoppers anonymously on 0800 555 111.
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