The 18-year-old man was arrested this morning on suspicion of murder; he remains in custody at a north London police station.
A murder investigation was launched following the fatal stabbing of Ahmed in Paddington Green, W2 at 9.13pm on Friday, 26 February.
Police, London Ambulance Service and London’s Air Ambulance were all called to the scene but despite their best efforts, 19-year-old Ahmed was pronounced dead at the scene.
Enquiries into the circumstances by homicide detectives from the Met’s Specialist Crime remain ongoing.
Anyone with information about the incident is urged to call 101 or tweet @MetCC with the reference CAD7919/26FEB.
You can also provide information, or upload footage, via https://mipp.police.uk/operation/01MPS21S04-PO1.
Information can also be provided to Crimestoppers, anonymously, on 0800 555 111.