A Fire and Emergency New Zealand spokesperson said crews were attending the fire alongside the airport’s own fire brigade.
They said five fire appliances, two ladder trucks and a command centre were at the scene.
Wellington Airport said the southwest pier and main terminal building had been evacuated and no injuries had been reported.
“Flights into Wellington have been temporarily diverted and passengers are advised to check with their airlines for information on specific flights,” it said.
Air New Zealand AIR.NZ, the airport’s largest carrier, said its flights in and out of Wellington were being held until further notice.
The fire was reported at around 7:15 p.m. (0715 GMT), according to Fire and Emergency New Zealand.
(Reporting by Lucy Craymer in Wellington and Christine Chen in Sydney; Editing by Aidan Lewis)

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