International airports across the country were hit by a “technical outage” affecting departures and arrivals on Friday morning.

The outage impacted SmartGate kiosks — automated border control points that use facial recognition ePassports to check travellers’ identity — the Australian Border Force (ABF) said.

It caused delays at immigration at Sydney Airport and long queues in Melbourne.

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Brisbane Airport was also impacted by the issue.

By midday the outage was resolved at all airports nationwide with the ABF saying “all systems are back online”.

“The cause of the technical issue remains under investigation,” it said.

“We wish to thank travellers for their patience during this incident.

Additional ABF officers were deployed to help manually process passengers while the outage was ongoing.