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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A main road in Birmingham is set to remain closed for the entirety of Sunday due to a "very serious" crash.
It will be a frosty start for many across the UK with slow-clearing mist and fog across parts of central and southeastern England.
The prime minister says she has proven the "doubters" wrong but still faces opposition from both sides of the Brexit line.