Detectives investigating the murder of a teenager at a shop in London's Oxford Street on Boxing Day have released CCTV images of people they want to speak to.

Seydou Diarrassouba, 18, was stabbed to death at the Footlocker Store on the busy shopping street.

Emergency services were called to the scene at 1.45pm on December 26, but the teenager, from Mitcham, was pronounced dead at the scene.

A post-mortem examination revealed he died from a single stab wound to the heart.

Detectives investigating the murder said they are keen to speak to a number of witnesses who were present at the time inside Footlocker and have yet to come forward.

They have released five CCTV stills - four from the Footlocker store and one from the nearby Forever 21 store - in a bid to track down the people to confirm whether or not they witnessed the incident.

Detective Chief Inspector Kevin Concannon, of the Met's Homicide and Serious Crime Command, said: "Whilst continuing to investigate this tragic stabbing last Boxing Day, it has become apparent that there are a number of witnesses to the incident who have not yet come forward and it is vital we are able to speak to them so that we have a clear understanding of what happened that day.

"I would encourage anyone who was there and who has not yet spoken to police to contact us."