Travellers at airports in Australia and New Zealand are facing delays after a major fault in a border security computer system.
Long queues have been reported at Auckland Airport and Wellington Airport, along with the Melbourne and Brisbane airports.
Nicola Hogg, Immigration New Zealand's general manager of border and visa operations, said the problem was an outage with the Advance Passenger Processing (APP) system.
"When passengers check in overseas, APP validates their entitlement to travel to or through New Zealand. This is a global system operated by SITA who are a multinational information technology company providing IT and telecommunication services to the air transport industry," she said.
"INZ has been advised by SITA that this is a global outage, affecting a number of countries. INZ is monitoring SITA's progress in getting the system up and running as soon as possible."
While there are delays, airlines are advising people they can still check-in manually.
"Due to the global outage of an IT system used by border authorities, Air New Zealand is currently reverting to manual check in processes for international departures," the national carrier said in a statement to Newshub.
"Customers are advised to proceed to check in as normal and keep an eye on the Arrivals and Departures page for the latest information."
Passenger Graham Underwood, who waited for hours to check in at Melbourne Airport, said the issue was affecting dozens of passengers.
"There's a massive queue at the premium check-in and at the kiosks," Underwood told Newshub.
He said he was in a queue of at least 80 people.
Passengers who had connecting flights were being told they may not be able to check-in or make their connection.
Underwood said he had been told there would be a delay of 90 minutes, but expects it to be longer.