Around 100 protesters, believed to be English Defence League supporters, are holding unplanned protests in two areas of Manchester.
There are also reports of a counter-protest by members of Unite Against Fascism in another part of the city.
Greater Manchester police have told ITV Granada that one person has been arrested on suspicion of a public order offence.
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Through the day we'll see plenty of sunny spells but there will be a risk of showers too as they filter down from the northwest.
Pilots say they are rostered in 'illegally' and feel fatigued from working too many hours.
The alleged hacking follows reports of similar attacks on other Democratic organisations, amid fears of state-sponsored hacking.