Gardaí arrested 19 people during disturbances overnight at the Fleadh Cheoil music festival in Clonmel.
The majority were arrested under public order offences. Some have been released and will appear before Clonmel District Court in September.
More than 250,000 music lovers, including some 10,000 musicians and 4,000 competitors in the All- Ireland competitions, were expected to attend the fleadh weekend.
The Fleadh Cheoil na hEireann is in Clonmel for the second year, starting tomorrow, with a week of concerts and ceilidhe, including Liam Clancy (today); Eileen Ivers and Micheal O'Suilleabhain (Thursday); Danú (Monday); a concert honouring Comhaltas pioneers (Wednesday), including Dr Tomas O'Canainn, this year's Ard Ollamh (Supreme Bard), who, along with Sean O'Se, will perform a Sean O'Riada tribute.