Actress Gemma Chan 'saw fatal stabbing in Putney'
An actress who has appeared in Doctor Who has described how she ended up face-to-face with a knifeman who had just stabbed a man to death.
Gemma Chan, who also appeared in Sherlock Holmes and is the partner of comedian Jack Whitehall, was giving evidence at the Old Bailey.
Schizophrenic Frederic Russell, 28, has been charged with murder but is not well enough to stand trial.
The jury must instead decide if he stabbed Colin Hammond in Putney.
The 65-year-old was killed last October as he walked down the street in west London.
Miss Chan told the court she was walking towards Putney Bridge underground station when she saw two men fighting on the ground.
The younger man, who had a goatee beard, was on top of an older man, kneeling on him and gripping his clothes around his neck with their faces a few inches apart, she said.
Miss Chan said she heard one of the men shout that he did not have money.
She said she retraced her steps and noticed that the younger man had his right hand pressed into the neck of the older man for about six seconds.
Miss Chan added that when the younger man pulled away, she saw there was a knife in his hand which she described as being about 12cm (5in) long.
The knifeman then got to his feet and walked along the road and disappeared out of view, she added.
The actress told jurors she went up to Mr Hammond, who was still lying on the ground and groaning and holding his neck, and asked him if he was alright.
She told the court that Mr Russell then reappeared and that the pair of them stared at each other for about three seconds before the road started to fill with people as a train had left Putney station.
Miss Chan said the defendant then disappeared in to the crowd of people.
She said she stayed with the victim until emergency services arrived later.
The case continues.