Police in Northern Ireland appealed for calm on Sunday and warned against returning to the "dark days" of rioting, following two nights of unrest in the troubled British-ruled region.

A crowd of 20 to 30 people launched an "'orchestrated attack on police" on Saturday evening, according to the authorities.

The unrest was reported in the Belfast suburb of Newtownabbey, which is an area dominated by supporters of the UK rule.

"In total, 30 petrol bombs were thrown at police and three vehicles were hijacked and set on fire," North Area Commander Chief Superintendent Davy Beck said in a statement.

What is the flare-up about?

The history of Northern Ireland has been marred by clashes between the unionists, who are loyal to the British government, and the nationalists, who would like to see the region break ties with London and join with the independent Republic of Ireland.

While violence has died down in recent decades, Brexit has fueled fresh tensions by reawakening old border disputes.

The unionists accuse London of pulling back in order to avoid a hard border with Ireland and the EU. Last month, the loyalists withdrew their support for the key 1998 Good Friday Agreement which ended the armed conflict. 

This week, some members of the faction were also enraged by the decision not to prosecute 24 members of the Sinn Fein party for breaking coronavirus guidelines.

The group attended a funeral of a noted member of the Irish Republican Army Bobby Storey in June last year.

What happened this weekend?

Police said that some of the rioters on Saturday were wearing masks and that older men were mixed with a group of youths. One 47-year-old man was arrested and remains in custody.

On the previous night, 27 police officers were injured during riots in Belfast and Derry/Londonderry, when protesters threw stones, bottles and fireworks at the security forces. Eight people were arrested.

What did police say?

On Sunday, Beck called on the community to provide the police with any information on the unrest, saying that the people of Northern Ireland "deserve better."

"I would appeal to those who are taking to the streets to stop immediately, their actions are causing nothing but harm and distress to the very communities they claim they are representing," he said. "No one wants to be dragged back to the dark days when rioting was a common occurrence on the streets of Northern Ireland."

dj/mm (AFP, AP)