Up to 30 people protested outside the Mansion House in Dublin last night, and one person was arrested.
Lord Mayor Hazel Chu says a peaceful event was taking place, which is organised at the house annually by the Irish Republican Brotherhood.
Four people were due to gather outside.
However, Hazel Chu says a far-right group "hijacked" the event, and the IRB event had to be moved to Stephen's Green as a result.
A woman was arrested for persistently breaching public health guidelines.
The Lord Mayor of Dublin says abusive comments were shouted at her by some of those demonstrating.
She said she did not feel unsafe and her daughter wasn't in the house at the time, but it was still 'surreal and uncomfortable'.
Lord Mayor Chu said everyone has a right to protest, but they should do so respectfully.
She said: “If people have issues with me and my policies or what I do in office… absolutely. But I don’t need people calling me names like ‘shape-shifting dragon’.”
"If you have an issue with my policy or what I’m doing with my job, bring it to my attention. If you disagree, protest yes… but I would ask you to do it respectfully, and be mindful of the fact that this is somewhere I’m living with my child.
"I don’t mind her seeing protests, but I do mind when things are being shouted at her mother that she can’t change at all.”
