A Ministry for Primary Industries (MPI) spokeswoman said last night details were still sketchy, but she could confirm "there were some ants found in an aircraft that travels backwards and forwards from Australia".
The ants were detected in the plane's hold, which caused "significant delays", the spokeswoman said.
"All the equipment in the hold and baggage had to be checked and treated."
The insects were collected and MPI staff would be analysing the ants, the spokeswoman said.
The MPI listed eight species of exotic invasive ants in a document describing species targeted under the "National Invasive Ant Programme".
The carpenter ant is the only one explicitly stated to be of Australian origin.
They are described as "large ants, up to 13mm long, ranging from dark to rusty-orange in colour".
"Carpenter ants are a major urban pest, named for their ability to chew wood.
"Look out for piles of coarse sawdust dropped by ants as they excavate their nests."
The document said these ants "do not sting but are capable of inflicting a painful bite".
