Billy Cox was shot in his home on Valentines Day 2007.
Police are making a fresh appeal for witnesses to the murder of a teenager in Clapham seven years ago.
Billy Cox, 15, was shot dead in his home on Valentines Day 2007, a crime which shocked the community on the Fenwick Estate where he lived.
Officers investigating are now hoping that anyone with information will pluck up the courage to come forward.
Billy left Acre Lane in Brixton at 2:36pm and made his way home. His sister, then aged 12, returned to their home and found her brother dying.
A friend helped her give first aid while they waited for an ambulance but when a paramedic arrived, Billy was pronounced dead at the scene.
There were no signs of forced entry and it is possible he knew his attacker.
A post-mortem examination gave cause of death as a gunshot wound to the chest.
Detective Sergeant Peter Hine of Trident, said: “The murder of Billy Cox is an ongoing investigation for Trident.
“We remain hopeful that witnesses will come forward to assist in bringing those responsible to justice.
“As time passes people’s lifestyles and allegiances can change and these people may want to help us get justice for Billy’s family. Trident has years of experience and I can assure anyone who does want to help that they will be protected.
“After seven years, we believe that anyone who knows who killed Billy Cox should feel that they can tell police what they know. We will treat all calls in the utmost confidence and urge you to pick up the phone, for the sake of Billy’s family.”
Billy’s aunt, Maureen Salkilld said she hopes justice is done before another life is taken.
“Every year we hold a memorial service for him, not that there are many days when he is not in our thoughts.
“From that fatal day to this, it has deeply affected his whole family. No matter what the circumstances, no-one deserves to die the way he did.
“As yet the people that know who committed the crime have not spoken out; Billy was very loyal to his friends, so we ask that his loyalty be returned.”
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