A man has been arrested over the murder of a 17-year-old boy who was stabbed in the neck.

The 30-year-old man was arrested at an address in Sydenham, south London, and is in custody at a south London police station.

Nilanthan Murddi died after receiving a single stab wound to the neck during an incident in Croydon, south London, early on Saturday morning.

Police believe a man who argued with Nilanthan and his group of friends near a set of traffic lights may have returned shortly afterwards to carry out the attack.

Scotland Yard said an allegation had been made that racist language was directed at the group in the early stages of the incident, which took place at about 1am on Sumner Road.

Officers said they regarded this as a possible motive for the 17-year-old's murder.

Detective Chief Inspector Tim Grattan-Kane, leading the investigation, said: "We remain dedicated to finding and prosecuting the person responsible for Nilanthan's murder, irrespective of whether the incident is racially motivated or otherwise.

"However, should that prove to be the case it only serves to further highlight the tragedy of this young man's murder."

Police are appealing for a taxi driver to come forward who, they believe, had the suspect in his cab 30 minutes before the murder.

They are looking for a blue Ford Mondeo or an older style VW Passat which had a TfL sticker in the back to show it was legally registered. Detectives are also asking people who were at nearby shops at the time to contact the incident room.