A 46-year-old female police officer from Scotland Yard's Diplomatic Protection Group was arrested over alleged leaks to the media linked to the Andrew Mitchell "plebgate" affair, the Metropolitan Police said.
A 46-year-old male officer arrested yesterday has been bailed to return on a date in March.
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The advertising watchdog has ruled the "beach body ready" campaign was not offensive or socially irresponsible.
Britain is set for the hottest day of the year today, with temperatures forecast to hit up to 34C (93F).
The Airports Commission is to publish its report and recommendations on whether an extra runway should be built at Gatwick or Heathrow.