A power cut in Seaham left more than 3,000 customers without power this morning.
Northern PowerGrid confirmed that 3,447 customers were affected by the cut at 9.02am in the SR77 postocde area.
By 9.45am 898 customers were back on supply and a further 1,943 customers had their power restored by 9.57am.
Engineers are currently on scene and originally aimed to have everyone back on supply by 11.45am but seven customers are still without power nearly eight hours later.
A Northern PowerGrid spokeswoman said the remaining seven customers should be back on supply by 6pm .
Engineers investigating the incident said the cut was caused by an underground cable fault on the network but it is not known why the fault was caused.
A spokeswoman said:”We want to apologise for the disruption caused and will get everyone back on supply as quickly as possible.”
Customers who want an update can use the Northern PowerGrid power cut checker by visiting: www.northernpowergrid.com