Nightly outbreaks of street violence in Northern Ireland must stop before somebody is killed, Irish Foreign Minister Simon Coveney said on Thursday, calling on political and community leaders to work together to ease tension.
The region's devolved government will hold an emergency meeting later on Thursday to be briefed on an escalation of rioting overnight with sectarian clashes, continued attacks on police and the setting alight of a hijacked bus.
The violence comes amid growing frustration among many pro-British unionists at new post-Brexit trade barriers between Northern Ireland and the rest of the United Kingdom that many warned could be a trigger violent protests.
"This needs to stop before somebody is killed or seriously injured," Coveney told national broadcaster RTE, describing the spreading of violence to an interface between unionist and Irish nationalist communities as "particularly worrying".
"These are scenes we haven't seen in Northern Ireland for a very long time, they are scenes that many people thought were consigned to history and I think there needs to be a collective effort to try to diffuse tension."
Large groups threw fireworks, bricks and petrol bombs at each other from either side of one of Belfast's so-called "peace walls" that have divided the two communities in parts of the city since the violent "Troubles" began more than 50 years ago.
Parts of the region remain deeply split along sectarian lines, 23 years after a peace deal largely ended the bloodshed. Many Catholic nationalists aspire to unification with Ireland while Protestant unionists want to stay in the United Kingdom.
British Prime Minister Boris Johnson said he was "deeply concerned" by the violence, which has injured dozens of police officers in recent days. At least seven officers were wounded on Wednesday, the chairman of the Police Federation for Northern Ireland, Mark Lindsay, told BBC Northern Ireland.
While Northern Irish politicians from all sides condemned the clashes, the Irish nationalists and unionist rivals that lead its compulsory power-sharing coalition blamed one other.
Sinn Fein and others have accused the Democratic Unionist Party (DUP) of First Minister Arlene Foster of stoking tensions with their staunch opposition to the new trading barriers that many unionists feel erases part of their UK identity.
The DUP in turn have pointed to a decision by police not to prosecute Irish nationalists Sinn Fein for a large funeral last year that broke Covid-19 regulations. They also called for Northern Ireland's police chief to step down over the matter.
Coveney, who spoke to Britain's Northern Ireland minister on the violence late on Wednesday, said a number of factors were inflaming division and polarisation, and that the post-Brexit protocol arrangements were clearly one of them.
"I don't believe a political vacuum where we are all speaking separately rather than together with one voice is the way to show leadership in our community," Northern Ireland's Justice Minister, Naomi Long, a member of the cross-community Alliance Party, told the BBC.