Eight police officers have been injured by rioting loyalists in east Belfast.
One needed hospital treatment after a series of violent attacks linked to protests over the decision by councillors to restrict the flying of the Union Flag over City Hall. He was later released.
At one stage a road was blocked by a burning car in the Templemore Avenue area.
Hooded and masked gangs pelted officers with bricks, bottles and petrol bombs.
Police said there were two arrests.
Motorists were diverted away from the disorder - the latest outbreak since last month's City Hall decision.