All the children involved in the National Yacht Club junior regatta at Dun Laoghaire have been accounted for after more than 90 boats were capsized by a sudden squall.
About 110 children are thought to have been thrown into the water but the Dun Laoghaire and Howth lifeboats and the Irish Navy's LE Aoife were on hand to assist with the rescue operation and all participants are now believed to be safe.
AA Roadwatch is warning motorists of major disruptions to traffic as a result of the incident.
A number of emergency service vehicles are at the West Pier in Dun Laoghaire.
Gardaí are advising motorists to avoid the coast roads.