"It was me."
Margaret Anderson, 50, was giving evidence at the trial of her son Lee Anderson, 31, who denies murdering Javaid Ali at his Sunshine Grocers store in Green Road, Paisley, on June 15, last year.
Mrs Anderson told prosecutor John Scullion that her son made the remark, which she claimed was a joke, while they were in the kitchen of her home in Foxbar, Paisley.
She was asked if she thought Anderson had confessed to injuring Mr Ali, 48, and replied: "No. A couple of minutes later he said 'I'm sorry mum I didn't mean to give you a fright'."
She also told the court that she contacted Crimewatch after a programme featuring the death of Mr Ali was broadcast in July 2012.
She said it was because police were looking for someone wearing a grey tracksuit who was seen running away along a path near to Green Road.
Mrs Anderson said her son had clothes like that and she wanted him to be ruled out.
The trial continues.