Detectives from Hertfordshire Police are urgently seeking to trace 22-year-old Jack Wall in connection with the disappearance of Amelia Arnold, who was last seen on Wednesday.
Wall, of Hadrian's Walk, Stevenage, has been urged to hand himself in to police, who have also issued an appeal for sightings of a Citroen Berlingo van as part of their inquiry.
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A rather cloudy start on Saturday for many areas, still with some occasional rain or drizzle across parts of the south and west.
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