During the prosecution's opening statements today, the court heard how William Jones walked to Claude Road that night in April from his father's house nearby, looking for his girlfriend, who he believed to be with another man at a property in the area.
The prosecution said Mr Jones admits being in Claude Road, and knocking on the door of Peter Lewis' flat. They said he will claim that Mr Lewis threatened him with a knife, which he grabbed and hit him with, accidentally stabbing him.
William Jones denies murder, and the case continues.
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It will be wet and windy this evening and through much of tonight with some heavy rain at times.
Welsh golfing legend Ian Woosnam has set his sights on securing a home victory at the Wales Senior Open in Newport.
It will be a bright start to Saturday, with some sunny spells. However, cloud and rain will reach the far west by late-afternoon.