Gardaí intervened last night to break up a large 'car meet' after up to 800 people had gathered at the event in Co Cork.
They said they received a report that hundreds of people had gathered at Eastgate, Little Island, in contravention of public health regulations.
Gardaí also said there were more than 250 vehicles in attendance.
In a statement, gardaí said: "There was very little evidence of social distancing, wearing of face coverings or general compliance with public health guidelines.
"Ages of participants included older males in their 30s/40s, some accompanied by young children, but mainly males and females in their 20s.
"Participants had travelled from outside the greater Cork area and various parts of Munster."
One senior garda inspector described it as "a disgraceful gathering of persons, despite the health advice in the last few days".
The crowd was dispersed soon after gardaí arrived and there were no public order incidents.
One man was arrested for what gardaí called "drunkenness offences".