A teenager who stabbed a young man to death in a South Norwood park has been jailed for life.

Darnell Martin, 19, will serve a minimum of 19 years in prison for murdering 21-year-old David Darko in South Norwood Recreation Ground in January following a botched drug deal.

An Old Bailey jury found him guilty of murder yesterday.

During the trial Martin, of Sylvan Hill, Upper Norwood, claimed he had pulled out his knife and tried to ward off Mr Darko in self-defence after the supermarket worker had attacked him with a baseball bat.

The court heard he had been recruited to provide "muscle" for his friend Joshua Asante, also 19, who had arranged to meet Mr Darko to sell him cannabis.

Mr Asante, of Atlee Close, Thornton Heath, was cleared of both murder and manslaughter yesterday.

Sentencing Martin this morning, His Honour Judge Paul Worsley told the teenager: "You were there to provide the muscle if it was needed.

"When things went wrong you produced the knife and stabbed him to death... a single, terrible blow."

The judge acknowledged there was evidence that supermarket worker Mr Darko, of Canal Walk, Addiscombe, and his friend Ferron Fletcher had conspired to rob Mr Asante of cannabis worth £800.

He also accepted the teenager had not intended to kill Mr Darko on the night of January 23, and took into account his learning difficulties and the fact he had a "much lower" IQ than Mr Asante.

But he rejected Martin's claims to have acted in self-defence.

Judge Worsley said: "It was never any case of saying his was an accidental blow.

"When will young people learn, if they go out with knives at night, the prospect of injury or death will follow. It's something the courts have had to deal with over and over again."

The court also heard that, in his original defence statement, Martin denied stabbing Mr Darko and tried to pin the blame for carrying the murder weapon on Mr Asante.

Speaking after seeing her son's killer jailed, Mr Darko's mother Ivy Darko said: "I just... what can I do? At least some sort of justice has been served."

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David Darko

During the sentencing hearing this morning, prosecutor William Boyce read from impact statements provided by Mr Darko's parents.

Mrs Darko said her son had a "great smile which lit every room and warmed the hearts of those around him", and described him as a "hard worker" who was intent on fulfilling his dream of going to university to study railway engineering.

She said her son's death was "almost outside her reality," adding his younger brothers "still found it hard to deal and come to terms with the fact he has gone".

FROM JANUARY: Murder victim David Darko's mother: 'I forgive my son's killer'

Mrs Darko had been preparing to go to bed on the night of her son's murder when police officers accompanied by some of the 21-year-old's friends knocked at the door.

Against the advice of officers she went to South Norwood Recreation Ground and "the trauma of what she saw there - David lying dead in the park - is something she will live for ever", Mr Boyce told the court. 

Mr Darko was found by a passer-by at about 7.45pm suffering “catastrophic injuries” having staggering from the spot where he was stabbed to another part of the park.

Despite the efforts of paramedics and “significant emergency surgery at the scene,” he was pronounced dead from his injuries an hour later after suffering shock and haemorrhaging from a single wound to the abdomen.

During the trial Mr Boyce described how Mr Darko was found “slipping in and out of consciousness and groaning” while holding a small rounders bat in his left hand emblazoned with the words “baseball star”.

The knife used to kill Mr Darko has never been recovered.

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A police forensics officer at South Norwood Recreation ground following the murder of Mr Darko in January

Mrs Darko's biggest regret, her statement read, was that her son had no "opportunity to say goodbye" to his family.

She "despaired about how David must have felt and the fear he must have experienced," and was distraught by the prospect that he had "died alone".

It was "an inexplicable pain" that his family "were not there to protect him or to comfort him," Mrs Darko added.

Since her son's murder she has struggled to sleep and her health has deteriorated, Mr Boyce said, while the cost of his funeral had caused their family financial difficulties.

She felt "numb" and "no joy" since David's death, with "no happy memories", her statement read, adding the trial of his killer had deepened her stress and grief.

In his impact statement, Mr Darko's father Lawrence said he had "not known what to do with his time" since David's murder, adding: "I just think about him lying in the park."

He recalled how his son, "who only ever wanted me to be proud of him," would meet him in Thornton Heath High Street before going to work "just so he could say, 'Hi Daddy'".

Mr Darko, who is separated from his son's mother, said he also had experienced difficulty sleeping and struggled to accept the fact of his son's death.

Before sentencing Martin, the judge praised the victim's family for the "dignified and reasoned way" they conducted themselves during the trial.

He also ordered that Emma Bashford, the member of the public who phoned 999 after finding Mr Darko lying in the park as she walked her dogs, should be paid £250 in public money as a "small token" of her public service.

In his mitigation before the sentencing, Martin's lawyer Jeremy Dean told the judge that his client "did not take the knife to the scene to commit any offence".

But Judge Worsley revealed that, even before the jury had returned their guilty verdict yesterday, in his mind "there was no question of self-defence arising at all - let alone it being reasonable".

Martin, who had remained silent and staring straight ahead throughout the sentencing, bowed his head as the length of his jail term was read out.

He showed little emotion as he was led away from the dock.

Detective Inspector Pete Timms, from the Metropolitan Police's murder squad, said: "This was not a chance encounter between David and Martin. The meeting was pre-arranged and somewhere along the lines there was a turn of events, I believe an intended robbery, which has led to David's death.

"I am pleased with the result that has been handed down today and I hope that this provides a small measure of comfort to David's loved ones."

A 19-year-old man charged with assisting an offender will stand trial at Croydon Crown Court on December 5. 

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