PSNI DEPUTY Chief Constable Judith Gillespie warned in her blog on Monday that public disorder will ruin people’s Christmas if caught.
On Tuesday morning, nine children, the youngest 11-years-old, are in police custody being questioned about alleged public order offences over the ‘Operation Shutdown’ Union flag protest on Monday night.
And if charged they could be remanded in custody by a youth court to spend Christmas behind bars.
The youths were all arrested in Lisburn where police said serious disorder erupted.
Five children, the young just 11, were arrested in the Hillsborough Road area.
Four more children – a 14-year-old, two 15-year-olds and one 17-year-old – were arrested in the Longstone Road area along with a 31-year-old man.
There were 15 people in total arrested after trouble erupted in parts of Belfast, Lisburn, Carrickfergus, Armagh and Portadown.
A PSNI officer was injured during unrest at Sandy Row in south Belfast where missiles were thrown. A car was also set on fire.
A 25-year-old man was arrested in the nearby Bruce Street area and an 18-year-old was arrested in the Blythe Street area of the city.
Police also came under attack from a group of up to 200 loyalist protesters in east Belfast as they dealt with disorder on the Lower Newtownards Road.
Unconfirmed reports said a journalist was attacked in the area.
A police officer was hurt in Portadown after a bottle was thrown in the Shamrock Park area of the town.
A man was taken to hospital after he was knocked down by a car on the Northway during a flag protest.
A 19-year-old man was arrested after a firework was thrown at police in Armagh during a protest attended by about 150 people.
In Carrickfergus, police are investigating after a number of protesters stormed the town hall where a public meeting was disrupted and a number of public representatives threatened.
A 30-year-old man was arrested in the Minorca Place area for public order offences.
Alliance councillor Sean Neeson said he and other councillors at Carrickfergus town hall were “subjected to sectarian abuse by four flag protesters”.
Colleague Noel Williams said the protestors carried out a “full frontal attack on democracy”.
Said the councillor: “They managed to enter the Council Chamber unhindered without facing any opposition and once inside subjected Councillors to verbal abuse, banging on desks and chairs with implements leaving many feeling threatened.
“It is unacceptable that the Town Hall was not under police surveillance, especially as violence has broken out at previous protests,” he said.
“People have a right to protest peacefully, but this incident tonight put many people’s safety at risk and must not be tolerated. We live in a democratic society and Councillors were meeting tonight as part of this process
“The Alliance Party has consistently called for protests like these to stop, letting politicians unite as they find a way forward. In the run up to Christmas it is local businesses and the community at large that are suffering.”
In Ballymena, a 20-year-old man was also arrested in the Cervilly Road area.
Around 80 protests took place across Northern Ireland as the row over the restriction of the flying of the Union Flag at Belfast City Hall entered its third week.
PSNI Assistant Chief Constable Dave Jones said: “While most of the protests were peaceful, the violence witnessed in some areas tonight is totally unacceptable.
“There were arrests this evening and more will follow as we now trawl through evidence gathered by officers out on the ground.”