After a rally against cuts in London, a break away group caused a scuffle during a smaller demonstration outside the Savoy hotel.
The scuffle began after a protester took a doorman's hat. The top hat was later returned to him. No one is believed to have been seriously injured during the incident.
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Sara Di Pietrantonio, 22, died in Rome on Sunday.
A vote to remain in the EU will see Brussels exert more power over the NHS, according to the Cabinet minister.
Tuesday: A cloudy, cool and dull day with outbreaks of heavy rain becoming lighter and patchier.