Belfast and other towns in the north of Ireland were plunged into chaos tonight following dozens of co-ordinated bomb alerts and other disturbances.
Roads have been closed across Belfast with vehicles abandoned close to PSNI police bases in the north and west of the city, officers said.
There is also disruption in north Armagh, where there has been unrest following a heavy police crackdown in the area.
The M1 motorway was shut close to the intersection with Lurgan, County Armagh, due to an abandoned hijacked vehicle.
Two cars were hijacked and set alight in the nationalist Kilwilkie estate in Lurgan. The nearby Dublin-Belfast railway line has been repeatedly closed as a result of trouble in the area in recent days.
Other incidents included the closure of North Queen Street close to the city centre because of an abandoned vehicle near the PSNI base and the closure of Hillview Road in the Oldpark area due to an alert.
Tennant Street, Blacks Roads, Stewartstown Road, Andersonstown Road and Upper Newtownards Road in the city were all closed for a period. following alerts at bases in Tennant Street and Woodbourne.
A lorry wa hijacked and set on fire on Upper Springfield Road, and a van which was burnt out close to Holy Cross church on the Crumlin Road in Belfast also caused disruption.
Sinn Féin Assembly member for North Belfast, Caral Ni Chuilin, blamed dissidents for the trouble. She said rival republicans had “no strategy”.
“These actions are wrong and counterproductive to anything that our communities want,” she added.
“I would like the spokespeople of those behind these alerts to come forward and explain how this will in any way achieve a united Ireland.”