Rowan Thomas-Williams' mother appeals over his killers
The mother of a 20-year-old who was shot dead following a row at a house party last year has appealed for help in finding his killers.
Rowan Thomas-Williams was shot in the chest in Harlesden, north-west London, and died the next day, 6 December.
His mother Ruth Thomas said she was "still in shock and always will be".
Detectives said they have faced a wall of silence over the killing, which is being treated as murder.
Det Ch Insp Graeme Gwyn from the Metropolitan Police said: "I am convinced that there are people in the local community who have important information or know who is responsible and I would urge those with information to come forward and assist us with our investigation."
He added: "Since Rowan's murder, allegiances may have changed and I am hoping that those who did not engage with us at the time of the incident are now in a position to do so.
"This was a callous and brutal murder and Rowan's mother and wider family have been left completely devastated."
A £20,000 reward has been offered for information leading to a successful prosecution.
Ms Thomas said: "The loss of my son is heart wrenching, words can not explain just how bad I feel.
"Rowan was my first born, we had that special bond, and he is and always will be my baby boy."
Two men aged 26 and 50 have been arrested on suspicion of murder and are on bail until January.