Loyalists staged a noisy protest in Ballymena, Co Antrim, last night as republicans held an internment commemoration march in the staunchly unionist town.
Several hundred loyalists played Lambeg drums as the march took place in a nationalist area of the town.
They then dispersed peacefully after a stand-off with riot police.
Some stones were thrown at police officers during a later incident in another part of Ballymena, but the PSNI praised community leaders for helping to avert serious trouble.
Loyalists vehemently opposed the march, which was arranged by republicans unaligned with Sinn Féin.
The run-up to the event, which was limited to the nationalist Fisherwick estate by the Parades Commission, has seen an massive upsurge in sectarian attacks against Catholics throughout north Antrim.
The attacks have become so frequent that Catholics living in the village of Ahoghill have been issued with fire blankets by the police in case of petrol bomb attacks.