"Armed police, with the assistance of the Eagle helicopter, then approached the vehicle," he said.
"Two people - a man and a woman - were taken into custody without incident and are assisting us with our inquiries."
No other details in relation to the incident - and what investigation the vehicle of interest is connected to - have been revealed.
"For operational reasons, police are not in a position to comment further at this time."
Police said that part of the motorway was closed "briefly".
Waka Kotahi NZ Transport Agency alerted motorists at 11.25am that lanes had since been reopened in both directions.
Motorists were told to expect delays until the incident had been fully cleared.