All air and sea ports have been put on alert for missing 14-year-old girl and 35-year-old John Bush.
Police say sightings suggest they are heading south from Yorkshire and that any move to leave the country would be "very foolish".
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The Democratic presidential candidate may also have shown his cards on his choice of running mate.
The US president also shared a post on Twitter accusing Dr Anthony Fauci of misleading the public over hydroxychloroquine.
Fears over an impending second wave of coronavirus dominates Wednesday’s front pages.