The officers are protesting against proposed changes to their pay and conditions.
Some 20,000 officers from all 43 forces across England and Wales are thought to be taking part in the first police march in the capital for more than four years.
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The puppy was taken to the RSPCA’s centre in Potters Bar where an X Ray revealed her spine was severely damaged.
Liberal Democrat Martin Elengorn was photographed by a Tory rival in the council chamber at Richmond upon Thames.
Dry and breezy with sunny spells on Saturday.