Stones, bottles and fireworks have been thrown at Irish police for two consecutive nights.
Protests have been taking place outside a hotel in Dublin housing asylum seekers.
Here is what you need to know.
What prompted the unrest in Dublin?
Large crowds of demonstrators gathered outside the CityWest Hotel in Saggart on the fringes of Dublin.
The protest followed the alleged sexual assault of a 10-year-old girl near the building in the early hours of Monday morning.
The demonstration on Monday passed without significant incident but turned violent on Tuesday night when a large group hurled bricks, fireworks and glass bottles at police.
A police van was also set on fire.
Some protesters carried placards with anti-immigrant slogans, and shouts of "get them out" could be heard.
On Wednesday night, a large crowd of protesters and police faced off again.
Justice Minister Jim O'Callaghan said a man had been arrested and appeared in court over the alleged sexual assault.
"Unfortunately, the weaponising of a crime by people who wish to sow dissent in our society is not unexpected," he said.
"Peaceful protest is a cornerstone of our democracy. Violence is not."
How have police responded to the Dublin riots?
Officers used pepper spray and water cannons to disperse the crowds on Tuesday evening.
Six people were arrested.
One police officer was treated for a foot injury.
Police Commissioner Justin Kelly condemned what he called "thuggery" by "a mob intent on violence."
Prime Minister Micheál Martin said there was "no justification" for the disorder.
Unrest follows Northern Ireland and Britain protests
Hotels housing asylum-seekers have attracted protests in Ireland, as well as in neighbouring Northern Ireland and Britain, often spurred by reports of crimes committed by residents and stoked by anti-immigration and far-right campaigners.
In November 2023, hundreds of anti-immigrant protesters looted shops, set fire to vehicles and threw rocks at police officers in central Dublin after three young children were stabbed outside a school.
AP/Reuters.