It's one of the most controversial road safety schemes of its kind. Today a 20mph speed limit has been imposed on 500 streets in Brighton. Similiar schemes have been introduced in other towns and cities - but not on this scale. Video report from Malcolm Shaw.
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Police are hunting a driver who knocked down and killed a woman outside a hospital before driving off.
Cloud and rain first thing but it will gradually dry up from the north west. Becoming bright in the west, staying quite cloudy in the east
Rain becoming more persistent overnight. Rain and cloud slow to clear tomorrow but becoming dry by the afternoon. Some brightness later