The Highways Agency said it decided to keep the Boston Manor Viaduct closed because during works it found a crack in a "sensitive location", which requires it to be kept closed until it is repaired.
Diversion on the A312 and the A4. Drivers are being advised to allow extra time for their journeys.
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A mobile DNA screening unit has been set up in a village where detectives are working to find a grandmother's killer.
Tuesday night's weather for the east of the region
Tuesday night's weather for the west of the region