It happened in Dorset Avenue last night when the victim was walking along the pavement with a friend.
They were both hit by a dark-coloured car.
One of the men was then stabbed in his lower body and is in a serious condition in hospital.
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Warm and sunny this evening but cloudier overnight with a few spots of drizzle possible later. Rather cloudy tomorrow but most places dry.
Police investigating the fatal stabbing of a man in Northampton want the help of the public tracking down two men and a mini car.
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