Six people were arrested at what police said was a "violent" protest outside an asylum seeker hotel in southwest Dublin on Tuesday, following allegations that a 10-year-old girl was sexually assaulted.
Ireland's government and police condemned the protests, which took place after local media reported that a 26-year-old man accused of assaulting the girl was an asylum seeker.
The Irish state police force, known as the Garda, said six people were arrested and officers were subject to "sustained violence" as protesters launched bricks, glass bottles and fireworks at the police.
"This was obviously not a peaceful protest," said police commissioner Justin Kelly.
"The actions this evening can only be described as thuggery. This was a mob intent on violence against Gardai," Kelly added.
At least 1,000 protesters gathered outside the Citywest hotel in Saggart, southwest of Dublin, near the location of the alleged assault.
An AFP correspondent witnessed a police van set on fire as protesters carried Irish flags and chanted "get them out", while police attempted to use pepper spray to disperse the crowds.
Ireland and the UK have seen rising anti-immigration sentiment in recent years, with hotels housing asylum seekers common flashpoints for protests and violent riots.
Irish Prime Minister Micheal Martin condemned the "violent disorder" and "vile abuse" against police in a statement.
One officer sustained a foot injury, and protesters targeted the police helicopter with lasers, the Garda said.
The protest was organised by "disparate groups on social media, who stir up hatred and violence and encourage and entice others to get involved", according to police.
'Sow dissent'
The 26-year-old suspect appeared in court earlier on Tuesday charged in connection to the sexual assault, which allegedly took place at a location near the hotel.
The alleged victim was in state care at the time of the incident, with child and family agency Tusla confirming she "absconded" during a trip to the city centre and was reported missing.
Earlier in the day, Martin said the events of the alleged assault were "extremely serious and very, very grave".
Speaking in parliament, Martin acknowledged "the concern, anger and worry of many people throughout the country at what (is) alleged to have transpired here".
"Clearly, there has been failure here in terms of the state's obligation to protect this child," he added.
Justice and migration minister Jim O'Callaghan "condemned" Tuesday's disorder, noting the projectiles thrown at police.
"Unfortunately, the weaponising of a crime by people who wish to sow dissent in our society is not unexpected," O'Callaghan said in a statement.
In June, dozens of officers were injured in anti-immigrant unrest in Northern Ireland after two teenagers were arrested and accused of attempting to rape a young girl in Ballymena.
Police did not confirm the ethnicity of the accused, who had asked for a Romanian interpreter in court, prompting what authorities described as the "racist" targeting of homes and businesses by rioters.
