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 Westminster terror attack dominates the front pages of Thursday's newspapers.
A timeline of exactly what happened.
Tobias Ellwood, MP for Bournemouth East and Foreign Office Minister, attempted to save the life of the stabbed officer in Westminster.