A number of roads in Belfast have been blocked as part of a mass protest over the flying of the union flag.
The pickets caused disruption for rush-hour traffic, forcing bus operator Translink to suspend most of its Metro services into and out of the city centre.
Social media websites listed up to 60 protests across Northern Ireland, which started earlier this evening.
Roadblocks had been set up on at least ten roads, however the PSNI later confirmed that all routes across Belfast had reopened.
It is the 19th day that loyalists have taken to the streets to show their opposition to restrictions on flying the union flag over Belfast City Hall.
Most have been peaceful but sporadic violence has marred some of the demonstrations.
Meanwhile, two people were arrested after reports of disorder in east Belfast during the early hours of this morning.
Police said a group of about 15 men attacked houses in the Lower Newtownards Road area. A family left their home because of the attack.
A 27-year-old man was arrested for possession of an offensive weapon and is due in court in January. A 20-year-old man was arrested for riot.
Superintendent John McCaughan, of the PSNI, said: "Tensions are heightened; however, we would ask that people take a step back and consider the wider implications of engaging in any criminal behaviour."