Zaian Aimable-Lina was knifed in the heart shortly after 7pm on Thursday and died at the scene in Ashburton Park, Croydon.

A 15-year-old youth was arrested on suspicion of murder late on Saturday and remains in custody, Scotland Yard said.

Another boy, also 15, has been released on bail to a date in January after being arrested the previous day, also on suspicion of murder.

A post-mortem that took place on New Year's Day gave Zaian's cause of death as a stab wound to the heart, the Met Police added.

Officers have said he was from the local area in south London and his family are being supported by specialist officers.

Detective Chief Inspector Richard Leonard said Zaian's death had sent "shockwaves through the local community".

A second fatal stabbing, during which a 16-year-old boy was killed in Yiewsley, west London, took place less than an hour later.

It was the 30th teenage homicide in London in 2021 - a new record.

Anyone with information is asked to call the incident room on 020 8721 4622, or 101, quoting reference CAD 5443/30Dec21. Those who wish to remain anonymous can call Crimestoppers on 0800 555 111.