A 41-year-old local man, believed to be the driver of the car, was arrested for grievous bodily harm at the time.
This is now being treated as a homicide investigation by Surrey and Sussex Major Crime Team working in conjunction with colleagues in West Sussex Division.
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Families across the South East are still anxiously waiting for news of their loved ones in Nepal.
Tuesday night's weather for the east of the region
Tuesday night's weather for the west of the region