The youngest woman Tube driver also likes to "keep it in the family".

BBC: London

He said the Tube driver told passengers he was unable to stop at West Ham station due to "police investigations".

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Those require a driver to breathe into a tube, much like the breathalyzers police ask suspected drunken drivers to use.

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Her father, Phelim, 38, is a manager at Wembley Park station, her 17-year-old brother Phelim is a trainee at the maintenance firm Tube Lines and her godfather is a driver on the Jubilee Line.

BBC: London

Passengers on the train in front were instructed by their driver to move through the carriages to the front of the tube as it passed through stations as the runaway gained on them.

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