Passenger backlogs clearing after massive delays at international airports

The delays were caused by a technical outage affecting SmartGate kiosks around the country, the Australian Border Force (ABF) said.

But by midday on November 8 the systems at all airports were back online.

ABF officers were deployed at immigration checkpoints to manually process passengers while the technical outage was addressed.

"The cause of the technical issue remains under investigation. We wish to thank travellers for their patience during this incident," an ABF spokesperson said.

A traveller at Sydney Airport said the line looked as though it was "the length of the international airport, twice over" before 10am.

Airline staff were telling passengers to report to the front of the line ten minutes before their boarding time if they hadn't yet passed the security checkpoint, the traveller said.

A spokesperson for Sydney Aiport apologised for the disruption saying patience was appreciated as the issue was being resolved.

"Passengers travelling today are encouraged to check with their airline regarding the status of their flight, and leave plenty of time when travelling to the T1 International Terminal."

The same outage was affecting travellers at Melbourne Airport on November 8.

A spokesperson said, "There are currently no cancellations or major delays at this stage".

Only one international flight was scheduled to leave from Canberra Airport on November 8 and a spokesperson said there were no delays.