People were being urged to ring 101 for emergencies on Sunday morning as 999 calls were not connecting to a number of police forces and fire services.
The warning was sent out after a technical fault affected the 999 calls. Durham Constabulary and the Tyne and Wear Fire and Rescue Service were among those to issue alerts.
They were urging people to ring 101 in an emergency until further notice. Durham Constabulary said: "We are currently experiencing issues with our 999 system, if an emergency and you are unable to dial 999 please use 101. If you have a medical emergency please dial 111. We are working to get this resolved."