Gardaí are trying to bring order to the Dublin seaside resort of Portmarnock this evening, after crowds of young people arrived at the town's beach to take advantage of the good weather.
More than a thousand people were estimated to be on the beach, and a Garda spokesman said a small number of young people were causing trouble.
Reports from people in the area suggest the garda helicopter and a large number of squad cars have been dispatched.
Meanwhile, Irish Rail has confirmed that its 16.14 Drogheda to Pearse service had to stop at Portmarnock because a group of young people on board the train were causing problems for the driver, and other passengers.
A press officer said that the youths were drinking and running amok - Irish Rail's security team contacted the gardaí, who attended and removed the offenders.
The train was delayed for 10 minutes.