Two men have been arrested in relation to the apparent Saturday car bombing in Londonderry, Northern Ireland police reportedly said. Authorities said that a republican dissident group, the New IRA, might be behind the attack, according to the BBC. While there is occasional violence involving minor splinter groups in the once-contentious region, car bombings are now rare. The bomb, which exploded outside a courthouse, did not appear to cause any injuries, authorities have said. The New IRA stands opposed to the 1998 peace accord that brought an end to some 30 year of upheaval in the British-run region, which left approximately 3,600 people dead. Law enforcement officials both in Northern Ireland and Ireland have voiced concern that returning to a more stringent border after Brexit could encourage militant groups, per reports.