“I would appeal to motorists who may have been travelling along this stretch of the A40 at this time, or pedestrians who may have been using the Holton over-bridge to contact police via 101.”
If you don't want to speak directly to the police you can contact the independent charity Crimestoppers anonymously on 0800 555 111 or online.
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Friday morning's forecast for the east of the region
Friday morning's forecast for the west of the region
A new safety system at the Dartford Crossing will turn around vehicles considered too unsafe to travel through the tunnel.