Police are investigating a technical fault with the 111 system which prevented people from reaching emergency services in the early hours of Sunday morning.
The nationwide fault affected people trying to get through between midnight and 12.45am. Callers received an automated message saying the system was overloaded and could not proceed any further.
Acting national manager for Communication Centres, Inspector Mal Schwartfeger said the fault was with the Police system rather than Spark.
The Spark initial call answer point identified the issue and alerted Police. Standard business continuity processes were put into practice immediately.