A prosecution witness has told a court he "did not know" whether he had told police who killed a father in Mitcham.

The witness, who cannot be identified for legal reasons, was due to give key evidence in the trial of Dwayne Roberts, who is accused of stabbing the Tamil man to death outside a community centre in South Lodge Avenue, Pollards Hill, on October 22, 2011.

The witness only agreed to step inside the Old Bailey courtroom yesterday after a guarantee he could give evidence from behind a screen, unable to be seen by the defendant nor members of the public.

Last week, the jury was told how Mr Roberts had hid the murder weapon near his youth hostel home in Mitcham Lane, Streatham.

Police discovered where the knife was after two associates of Mr Roberts both told police he was the killer and that he was carrying two knives that evening.

But one of those witnesses refused to give evidence in court yesterday, with no reason given to the court for why.

The prosecutor, Sarah Whitehouse, was unable to get the witness to confirm anything other than his name, which may not be disclosed due to reporting restrictions.

She asked: "Can you read?"

He replied: "No."

She asked: "Do you remember being asked questions about the community centre?"

He said: "No."

She asked: "Do you remember making a witness statement about it?"

He said: "No."

At this point, Mr Roberts was seen laughing in the dock as the exchange unfolded.

After a short break, Mrs Whitehouse tried again to get the witness to give answers, but to little avail.

She asked: "I don't know if you think everyone in this court is stupid. You can read can't you?"

He replied: "No."

She said: "You told the police that you had seen Dwayne Roberts stab the man outside the community centre."

He said: "I don't know."

She asked: "You don't know what you told the police? That is the reason you are in court this morning... Are you afraid?"

He replied: "No."

She asked: "Is it because you feel you shouldn't have dropped [Mr Roberts] in it?"

He said: "No."

Mr Roberts denies murdering 28-year-old Akilankumar Kanthasamy, outside the New Horizon Centre, in South Lodge Avenue.

Last week, Mr Kanthasamy was described as an innocent man "in the wrong place at the wrong time" when he was stabbed once in the heart.

Mr Kanthasamy had chanced upon a street fight between groups of Tamil and black teenagers had taken place after cannabis was stolen from the group of Tamils.

The trial continues.

Coverage of the trial

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