The closure is due to a network switch, as part of the move to the new National Children's Hospital
A major IT upgrade will see the emergency department for children at Tallaght Hospital in Dublin temporarily shutting down.
The facility will close from midnight, reopening next Tuesday morning.
The network switchover is part of the move to the new National Children's Hospital.
People are being advised to go to Crumlin Hospital or book an appointment at Connolly Hospital instead.
Longer wait times at both hospitals are to be expected.
The inpatient and outpatient facilities at Tallaght will remain operational.

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