Detectives investigating the murder of Thornton Heath teenager  have said the 16-year-old boy who stabbed him to death on New Year’s Eve may not be charged with murder because he “acted in self-defence”.

Kyall Parnell, 17, died from a  single stab wound to the heart, at the hands of a 16-year-old, who had told police he had been stabbed before in attacks involving Kyall. 

Kyle died  in Norwood Road near the junction with Station Rise, Tulse Hill, at around 10.43pm on Sunday December 31 after an altercation on the No 68 bus travelling towards Herne Hill. His attacker was arrested and bailed.

Detective Inspector Ian Titterrell, from the Metropolitan Police’s Homicide and Major Crime Command, told Southwark Coroner’s Court that Kyall was with a group of friends on a bus when another group including the unnamed 16-year-old boarded.

DI Titterrell, said: “As those three males walked up to the top deck where Kyall and his friends were sitting, there was immediately a confrontation.

“The three males who had just got on at Tulse Hill got off the bus and they were pursued by Kyall and his friends, with two of the males seeking refuge in a convenience store.

He added: “Witnesses had seen the chasing group in possession of knives and Kyall is seen in very clear CCTV on the route 68 bus to approach an individual in a very aggressive manner with his hand placed towards his left hip area – there was a suggestion of something glinting.

“A knife was found on Kyall afterwards. The male, fearing for his safety, has stabbed Kyall once in the chest. This stab wound pierced the heart and it’s that that led to his death.”

DI Titterrell said that during the confrontation, Kyall’s friends told him to “stab him, finish him off”, which the younger boy claimed caused him to take out a knife from his bag before plunging it into the victim in an attempt to protect himself.

DI Titterrell said the Tulse Hill investigation was ongoing but at this stage the Crown Prosecution Service had indicated that it would not charge the attacker with a homicide offence because of the “real issue” of self-defence.

The inquest was opened and adjourned to a date to be fixed.

Anyone who witnessed this incident or has information should call the incident room on 020 8721 4005 or contact via Twitter @MetCC

To remain anonymous, call the independent charity Crimestoppers on 0800 555 111 or online at crimestoppers-uk.org