The Ministry of Health has asked travellers flying into New Zealand to monitor their health after a "reported green zone breach" at Brisbane airport.
The breach occurred at the Hudson Café where two individuals from a red zone country were in the cafe at the same time as green zone passengers.
The three flights affected are Air New Zealand NZ 202 from Brisbane to Christchurch which arrived around 4.30pm on Thursday, Air New Zealand NZ 146 from Brisbane to Auckland which arrived at 5.30pm and Qantas QF 135 from Brisbane to Christchurch.
Queensland Health told the Ministry that the two red zone passengers were wearing masks, maintaining social distancing and are not symptomatic. The public health risk is deemed as low.
The two red zone travellers returned negative COVID-19 test results prior to departure from their home country but a second test result from swabs taken on Thursday shows a weak positive for one traveller.
Green zones are areas of the airport where only travellers from New Zealand or Australia can go. Red zone areas include travellers from all over the world including COVID-19 hotspots.
The aim is to keep quarantine free travellers separate from passengers arriving from countries with COVID-19.
Brisbane Airport said in a statement the breach was due to human error.
Two passengers arrived from red zone Papua New Guinea, and headed through screening to transit "as per normal process".
"Initial review of CCTV indicates that at approximately 9.55am, these passengers were incorrectly allowed into the green zone'," the statement reads.
By 11:20am the travellers were seated at the cafe. They used the bathroom and visited another retailer before being located by airport staff.
They were in the green zone for just under two hours. During this time three green flights departed to New Zealand.
"At this stage, it is believed only a handful of passengers were in the vicinity of the two 'red' passengers at any time.
"BAC [Brisbane Airport] is conducting a thorough investigation and unreservedly apologises for this human error."
Each plane affected by the breach has been met by officials alerting them to the breach and have been provided with advice for monitoring their health.