Vicky Pryce, 60, emerged from East Sutton Park Prison near Maidstone, Kent, via a back exit.
The mother-of-five was driven away with her lawyer Robert Brown, pursued by press photographers who been camped outside the Category D open jail for women and young offenders.
The ex-wife of former Cabinet minister Chris Huhne's has served around a quarter of an eight-month sentence for taking speeding points for him.
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A new mother gave birth to her baby son at the side of a motorway – much to the surprise of passing police officers.
Hong Kong's most prominent student activist has joined activists in the city after being freed from prison.
Foreign royals will be among those at Windsor Castle for the occasion.