A witness kept quiet for 17 years about what she saw on the day of an alleged murder because she did not want to get involved, a court has heard.

Amelia Clark, 54, said she had spotted the man accused of killing Surjit Singh Chhokar in 1998 put something into his jacket pocket near the scene of his death.

Mrs Clark, from Wishaw, North Lanarkshire, told the court that as she watched Coulter zip up his jacket she heard a woman screaming hysterically: "He's been stabbed. He's been stabbed. Phone the police."

She was giving evidence at the trial of Ronnie Coulter, 48, from Wishaw, who denies murdering Mr Chhokar by stabbing him in Garrion Street, Overtown, North Lanarkshire, on November 4, 1998.

The jury at the High Court in Glasgow heard Mrs Clark only came forward with her evidence in May last year, almost 17 years after Mr Chhokar's death.

Mrs Clark, whose son Derek Clark, is serving 15 years for attempting to murder Ronnie Coulter's mother Mary Coulter, denied she was doing this for revenge.

She said: "I didn't want to get involved, I didn't want anything to do with it," adding that was why she had not told the police what she claims to have seen.

Mrs Clark told the court that she was in bed on November 4, 1998, when she heard the sound of running footsteps and then Mr Chhokar's partner Elizabeth Bryce shouting: "Leave him alone."

She said she got out of bed and looked out her window without putting on the light.

Mrs Clark said she saw Andrew Coulter standing alone at the end of the street and Ronnie Coulter and David Montgomery together.

Prosecutor Alex Prentice QC asked: "What did Ronnie Coulter and David Montgomery do?"

She replied: "They got to the end of the road and stopped and Ronnie lifted his hands. There was a street light. He turned and put something in his jacket.

"He zipped his jacket up and then he walked towards Main Street. As I was watching him I heard hysterical screaming 'he's been stabbed, he's been stabbed'."

When asked who was screaming, she replied: "Elizabeth Bryce."

Mr Prentice asked: "Did you see anything in his hands?"

Mrs Clark replied: "No, I didn't." She told the court she dialled 999.

Referring to Mrs Clark's son conviction, Mr Prentice asked her: "The injury to Mrs Coulter was a very, very serious injury?" She replied: "Yes."

Mr Prentice then asked: "It was a significant blow to the face which resulted in disfigurement and life-threatening injuries?" Mrs Clark replied: "Yes sir."

The prosecutor then added: "Has that anything to do with your evidence," and she stated: "No. It has nothing to do with it."

Under cross-examination by Donald Findlay QC, he said: "This time you say you are telling the truth. This is simply a revenge attack." She replied: "Not true, sir."

Mrs Clark was read out details of her son's crime by Mr Findlay. She told him: "He deserved to go to prison for what he did."

Mr Findlay asked Mrs Clark if it was coincidence that she spoke to police after her son was convicted and she replied: "They told me I had to come to court to give evidence. I said I'll not go on oath and tell lies. I will say what happened."

Ronnie Coulter has lodged a special defence to the murder charge blaming his nephew Andrew Coulter and David Montgomery.

Both men in evidence denied having anything to do with the killing of Mr Chhokar.

Ronnie Coulter denies all the charges against him. The trial before judge Lord Matthews continues.