Police in the North came under attack for the second consecutive night as violence flared following Orange Order parades in Belfast.
Petrol bombs, bricks, bottles and fireworks were hurled at officers and cars were set alight in the city's northern district of Ardoyne, which has a history of sectarian clashes.
Police in riot gear fired baton rounds and water cannons at crowds of around 200 in the Estoril Park and Brompton Park areas after their lines came under attack from masked youths on Tuesday evening.
Some officers were set alight briefly when hit by petrol bombs and targeted by lasers, while a local photographer was hit by a baton round, the PSNI said. Several officers were also injured and vehicles hijacked, the force added.
The rioting followed a nationalist protest march held to coincide with a loyal order parade through the residential sectarian interface to mark the Twelfth commemorations.
Trouble also spread to other parts of Belfast with disturbances in the Stewart Street area of Belfast city centre close to the mainly-nationalist Markets area. Stones and missiles were thrown at police and two parked vehicles were set on fire. A member of the public was hit by masonry. Three juveniles and two adult males were arrested on suspicion of riotous behaviour, according to police.
North Belfast Democratic Unionist MP Nigel Dodds condemned the rioters. "These people have been intent on attacking the police and wreaking havoc in their own community. Such violence is senseless and has clearly nothing to do with protesting against a parade but is just futile rioting," he said.
Police said calm was restored to the area during the early hours.
Away from Belfast, Derry, Armagh City and Ballymena, Co Antrim, also experienced public disorder. There were also disturbances in Newry, Co Down, when youths threw stones and set tyres on fire.
In Derry, crowds gathered and a van was set ablaze on a flyover close to Free Derry Corner. Police said a 14-year-old youth was arrested on suspicion of riotous behaviour with officers recovering a crate of petrol bombs. Seven males were also arrested for riotous behaviour. And in Armagh City youths burned tyres and hijacked a car, police added.