The Irish Guards' regimental mascot, Conmeal the Irish wolfhound, was given his own sprig of shamrock by the Duchess of Cambridge.
The St Patrick's Day tradition dates back to 1901.
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Police in Greenwich are trying to identify a man after an assault on an elderly woman in Plumstead.
Relatives of those killed in the Hyde Park attack 35 years ago marched in central London to bring an accused bomber to justice.
A new system will allow authorities to track private drones as research finds the heavier flying gadgets could smash plane windscreens.