"BT will continue to investigate these problems on Friday 7th September, moving their investigations from the core network to the links with the wider internet. More tests and some changes will happen overnight and during Friday."

The organisation added that Northern Grid and BT understand the importance of reliable and effective internet access, and promised that everything is being done to rectify the problem.

"A fault within the Northern Grid network is affecting internet services in some local council offices and schools in the North East. Voice services are unaffected," said BT in a statement emailed to Computerworld UK.

"We are sorry for the inconvenience and are working to restore normal services as quickly as possible."

Northern Grid is a not-for-profit, regional broadband consortium that is owned by Hartlepool, Middlesbrough, Darlington, Redcar and Cleveland, Stockton, North Tyneside and South Tyneside.