More than 10,000 homes in south Dublin are without power due to a major fault.
ESB Networks said it understood the fault had incapacitated two electricity sub-stations; at Mount Merrion and Belfield, cutting power to those areas and to Carrickmines and Donnybrook.
Gardai have issued a warning to motorists using the N11 between the Nutley Lane junction and south to the Brewery Rd/N11 junction.
All road lighting and traffic lights along this stretch of road are not working and gardai are directing traffic at junctions. Extreme caution is advised.
The outage happened at 4.16pm.
An ESB spokesman said crews were currently determining the nature of the fault and it was not possible to say how long it will take to repair the fault.
