Traders are worried that a march later today in Belfast could affect business on what should be one of the busiest shopping days of the year.
A children's walk, Christmas party and Santa planned by a charity for youngsters with heart disease have already been cancelled.
Ulster Unionist Party leader, Mike Nesbitt MLA, called on protesters to stop now.
Anyone who attacks a police officer, anyone who riots, anyone who engages in illegal street protest, is disrespecting the values of the Union flag.
Stop now. You are losing the argument.
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Cloud and outbreaks of rain will ease away eastwards during the morning, clearing the east coast around midday with sunny spells developing.
Police and emergency services are attending the scene.