Some 5,000 homes and businesses are without power after severe gales battered parts of Northern Ireland.
Gusts of around 70 miles-an-hour and flying debris ripped down power lines, electricity poles and trees, leaving some roads impassable.
The worst affected areas are Counties Tyrone and Armagh.
Northern Ireland Electricity (NIE) said engineers and emergency crews were battling the stormy conditions in an effort to restore power but warned of further problems on the network as high winds continued to sweep across the region.
A statement said: “Damage has been caused by flying debris and high winds, including broken electricity lines and damage to poles and other equipment.
“There may also be further faults which have not yet been reported to Northern Ireland Electricity, and adverse weather conditions, which could cause additional faults, are due to continue for the next few hours.”
Meanwhile, the high winds have caused the cancellation of a number of ferry sailings.
P&O Ferries said all its services between Northern Ireland and Scotland had been suspended, while early morning Stenaline boats from Belfast to Cairnryan and Liverpool were also cancelled.
The adverse conditions have also impacted on the daily Rathlin island to Ballycastle service in Co Antrim.
The Police Service of Northern Ireland (PSNI) has warned motorists to exercise caution and said a number of roads in Counties Tyrone and Londonderry were blocked because of fallen trees and electricity poles.
The Foyle bridge in Derry has also been shut to traffic because of the gales.