A teenager has been found guilty of murdering South Norwood supermarket worker David Darko.

Darnell Martin, 19, of Sylvan Hill, Upper Norwood, stabbed Mr Darko to death in South Norwood Recreation Ground in January this year following a botched drug deal, an Old Bailey jury found today.

The teenager will be sentenced tomorrow at the same court.

Joshua Asante, also 19, of Atlee Close in Thornton Heath, was cleared of both murder and manslaughter.

Mr Darko was found by a passer-by at about 7.45pm on the evening of January 23 with “catastrophic injuries” having staggered 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.

The trial heard how 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.

Before the trial began Martin admitted stabbing Mr Darko but claimed he had acted in self-defence after the young man tried to attack him with a baseball bat.

The teenager, also known as Y.S or Stoner, claimed he had pulled out his knife and try to "ward off" Mr Darko, and did not even realise he had stabbed him until hours later.

During a search of Martin's house when he was arrested detectives found the coat he was wearing at the time of the murder, which matched witness descriptions provided at the scene of the crime.

Detective Inspector Pete Timms, of the Met’s Homicide and Major Crime Command 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."

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