This is a phenomena of mob violence which has been stoked up by individuals and social media.
PSNI Chief Constable Matt Baggott added it was fortunate nobody had been killed or seriously injured last night, and he praised police for doing a "magnificent" job.
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Paul Golding was arrested by police in Belfast earlier on Thursday while he was at court supporting deputy leader Jayda Fransen.
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A major error in paying disability and sickness benefits to 75,000 people is to be put right - at a potential cost of up to £500 million.