The father of a young man murdered in a South Norwood park during a botched drug deal has spoken of his anguish at his son’s “foolish death” after seeing his teenage killer jailed for life.

Darnell Martin, 19, will serve a minimum of 19 years in prison for killing 21-year-old David Darko in South Norwood Recreation Ground in January with a single stab wound.

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David Darko

During his Old Bailey trial Martin, of Sylvan Hill, Upper Norwood, claimed he had pulled out a knife in self-defence after David Darko attacked him and his friend Joshua Asante with a baseball bat on January 23.

Mr Asante, 19, of Atlee Close, Thornton Heath, was cleared of both murder and manslaughter last week.

Sentencing Martin on Wednesday last week, His Honour Judge Paul Worsley acknowledged there was evidence that supermarket worker David Darko, of Canal Walk, Addiscombe, and his friend Ferron Fletcher had conspired to rob Mr Asante of cannabis worth £800.

RELATED: Teenager Darnell Martin jailed for minimum of 19 years for fatal stabbing in South Norwood Recreation Ground

But this week David Darko’s father Lawrence, 62, refused to accept his “always smiling” son was involved in any conspiracy.

During the trial, the jury heard a voice note found on Mr Fletcher’s phone sent to David Darko the day before his death.

In the recording, he said: “Listen. Move is going down tonight. Don’t f*** up. Make sure you grab the food and wrap up the yout and bounce.”

Lawrence Darko said: “I know what he is going to collect...[but] it is Ferron that David is going to get it for, because he is his best friend.

“They should have gone together. It was a foolish thing for David to do if the story is true. It was a foolish death.”

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David Darko, top right, at Woodside Primary school in 1999. Photo: Lawrence Darko

The court heard Martin had been recruited to provide “muscle” after Mr Asante, who attended Archbishop Lanfranc school with David Darko and Mr Ferron, had arranged to meet the supermarket worker to sell him cannabis.

Lawrence Darko was spending the evening with friends at a Ghanaian restaurant in Selhurst Road that night when news filtered through of a stabbing in nearby South Norwood Recreation Ground.

But he did not know his son was the victim until he received frantic phone calls from friends and relatives the following day, as the news spread as far as his extended family in Ghana.

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Lawrence Darko looking at family photographs at his home in Kenley this week

Lawrence Darko, who is separated from David’s mother Ivy, has struggled to sleep or even watch television since his son’s sudden death, and said he still felt “his presence any time I am alone”.

And unlike his estranged wife, who publicly forgave her son’s killer in the days following the murder, Lawrence Darko said he was unable to feel any mercy for Martin.

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

Speaking at his home in Kenley, Mr Darko said: “I don’t forgive him. I have told my ancestors to punish him.

“The best thing is that he is going to suffer in prison. Whenever I’m drinking, I pour some on the floor and say, ‘Someone should be punished’.

“I want him to suffer. Even God won’t forgive. I’m a Christian, but I don’t pretend. For Darnell Martin, where he is, I know no one will forgive him.”

Sentencing Martin last Wednesday, Judge Worsley accepted the teenager had not intended to kill Mr Darko, and took into account his learning difficulties and the fact he had a “much lower” IQ than Mr Asante.

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Darnell Martin

But he added: “You were there to provide the muscle if it was needed.

“It was never any case of saying this 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.”

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

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

Before sentencing, prosecutor William Boyce read an impact statement from Mrs Darko that described her son as a “hard worker” intent on fulfilling his dream of going to university to study railway engineering.

She said David’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”.

Mrs Darko’s biggest regret, her statement read, was that her son had no “opportunity to say goodbye” to his family, and she “despaired about how David must have felt and the fear he must have experienced” on the night he died.

Judge Worsley praised the victim’s family for the “dignified and reasoned way” they had conducted themselves during the trial.

In his own impact statement, Lawrence Darko remembered 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’”.

Pacing around his flat yesterday morning, struggling to hold back tears, he added: “I know he’s in the hands of God. David was murdered how they killed Jesus Christ – he was knifed. I know God knows why – but for me, I don’t know why.”

Rifling through a pile of old family photographs, Lawrence Darko came across one of his son as a two-year-old, beaming for the camera, smartly dressed for the special occasion of his younger brother’s naming ceremony.

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Mr Darko said: “In all the pictures, he’s always smiling. Not knowing he’s going very soon.”

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