Auckland International Airport says a digger working outside the international terminal cracked a pipe and caused the evacuation of hundreds of passengers.
The international terminal was closed for nearly an hour on Thursday and reopened at about 5.45pm.
Tony Gollin from Auckland Airport says a gas pipeline was broken and fumes were going into the international terminal.
He says the fire service called for an evacuation of the building for safety reasons.
Mr Gollin says the gas supply was turned off to the area while the pipe was repaired.