At the height of the storm, the National Weather Service issued a tornado emergency for a number of areas in and around Oklahoma's capital city, with tornadoes reported outside Moore, near the suburb of Bethany, north of Union City and outside Tinker Air Force Base.

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The non-emergency number combines the old NHS Direct service with surgeries' own out-of-hours arrangements.

BBC: NHS postpones West region out-of-hours GP helpline launch

The emergency number used to call ambulances and the fire service was out of action for more than an hour.

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The Police Service of Northern Ireland introduced a single non-emergency number in 2005 - 0845 600 8000.

BBC: Non-urgent police calls 'go unanswered'

Tayside Police have praised the public for embracing the new non-emergency phone number, designed to take pressure off the 999 service.

BBC: Tayside Police praise public for embracing new 101 number