Gardaí arrested some 20 people in the town square in Listowel after a riot broke out at about 1am on Saturday during the annual harvest festival race meeting.
Thousands had flocked to the town for a night of entertainment on the penultimate day of the week-long race meeting.
One prominent local woman who witnessed the fight but who did not wish to be named said she was extremely frightened at the fracas which involved fighting between several women as well as men and which broke out in a number of locations, including in the the town square.
Garda re-enforcements had to be called in to help bring the situation under control.
A camper van worth about €60,000 was burned out in a suspected arson attack in a car park in the town centre.
