A teenager stabbed a young man to death in a South Norwood park after a drug deal went wrong, a court heard.

Darnell Martin, 19, of Sylvan Hill, Upper Norwood, has admitted killing 21-year-old David Darko but claims he knifed the supermarket worker in self-defence.

Mr Martin and Joshua Asante, 19, of Atlee Close, Thornton Heath, are on trial at the Old Bailey charged with murdering Mr Darko in South Norwood Recreation Ground on January 23 this year.

Prosecutor William Boyce, opening his case this morning, told the court the three men had met in the unlit park after Mr Darko, of nearby Canal Walk, arranged to buy “a large amount" of cannabis from Mr Asante.

RELATED: Darnell Martin and Joshua Asante, both 19, to stand trial accused of murdering South Norwood man David Darko

But mistrust between the pair, both former students at Archbishop Lanfranc school, led the deal to go sour, the jury heard.

Mr Boyce said: “It would seem things did not go well and a dispute seems to have arisen... leading to Mr Martin stabbing Mr Darko and killing him.”

On the first day of the trial today it emerged that Mr Martin, who the court heard had previously refused to answer police questions, admitted last Friday to knifing Mr Darko.

In his defence statement, Mr Martin denied prior knowledge of the drug deal and claimed he acted in self-defence after Mr Darko threatened the pair with a child’s rounders bat.

But Mr Boyce suggested Mr Martin had been acting as Mr Asante’s “muscle” for the arranged deal to “control what happened in the park [if there] was any issue to [Asante] getting [his] way”.

The prosecutor added: “There were comings and goings between [Mr Asante’s] car and the park, until eventually all three ended up in the park together.

“There seemed to be trust issues about the impending drug deal."

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Darnell Martin in 2013. Photo: Facebook 

After the stabbing the accused pair “ran away, leaving Mr Darko to die in the park, and drove away from the park in Mr Asante’s car,” the jury was told.

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.

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.

Addressing the jury, Mr Boyce said: “If you think Mr Martin unlawfully pushed, punched a knife into the abdomen of David Darko, you must think, as night follows day, he intended to cause him serious bodily harm.

“The only contact between the three of them was when Mr Martin pushed, punched a knife into Mr Darko’s abdomen.”

In the hours after the murder Mr Asante travelled to Coventry and then on to Liverpool, where he destroyed his phone, before handing himself to police three days after the murder.

Mr Martin was arrested three days later.

When police searched Mr Asante’s house they found £300 in cash, which he denied taking from Mr Darko.

In his police statement he said Mr Darko had been “persistent” about meeting in South Norwood Recreation Ground, adding: “I did not even want to go into the park. It’s extremely dark in there."

The court heard phone records showed Mr Asante, also known as Stitch, called Mr Martin before giving himself up - despite claiming in his statement the pair had never spoken on the phone and barely knew each other.

Mr Asante told police that on the night of Mr Darko’s death he had been driving to South Norwood Recreation Ground when he saw Mr Martin in the street and agreed to give him a lift to New Addington.

He described Mr Martin as a “random acquaintance from the area” who he only knew by the street name Y.S, adding: “My meeting with him that night was by pure chance…The only reason he was with me was because he asked if I could give him a lift in my car.”

Despite phone records showing the pair had been in contact in the month before and the days following the murder, Mr Asante said in his statement:“The person I have previously reffered to as Y.S I didn’t know by any other name. I didn’t know where he lives, I have never telephoned him.”

Mr Boyce told the court ”there had been a number of communications between the parties in the case,” including phone calls and WhatsApp messages between the two defendants and between Mr Asante and Mr Darko. 

Both Mr Asante, a shop assistant at Sainsbury’s in Richmond, and Mr Darko had also been in phone contact with another man, Ferron Fletcher, on the day before and the day of the murder.

Following his arrest in Liverpool, Mr Asante told police he had been receiving threatening messages from Mr Fletcher "claiming Asante had killed his friend,” the court heard.

The barrister also described how the defendants gave conflicting accounts about their relationship and their movements before and after the murder.

According to Mr Martin, Mr Asante had called him on the day of the murder asking him how to get to South Norwood Recreation Ground - despite Mr Asante living less than two miles away in Atlee Close, Thornton Heath.

Mr Martin said he had had met Mr Asante and directed him to the park and only realised a drug deal was about to take place after hearing him arguing on the phone.

When they arrived at the park they found Mr Darko wearing a hoodie and scarf that covered most of his face, according Mr Martin. 

The defendant began to believe Mr Darko did not have the money to buy the drugs and was planning to rob the pair, the court heard.

Mr Martin claimed to have pulled out a knife after Mr Darko threatened Mr Asante with the rounders bat.

He said he waved the knife it to try and ward Mr Darko off, before fatally stabbing his when he advanced towards him “swinging [the bat] wildly at his head”.

Both defendants deny murder.

The trial continues.

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