The NZ Defence Force is investigating what went wrong last night to allow a man to get onto its Whenuapai air base and make bomb threats, sparking a major emergency response.

Dozens of police and fire crews were sent to the northwest Auckland base as the incident unfolded from around 6pm last night. Armed police blocked the streets around the base.

A source at the base told the Herald a man had driven his car into a hangar and made bomb threats.

Man in custody after bomb scare at Whenuapai air base


Police said last night a man had been taken into custody and was talking with police.

A NZ Defence Force spokesperson said any intrusion into a New Zealand Defence Force camp or base was "a matter of concern".

"In the wake of last night's incident we will conduct an investigation to establish what occurred, how it occurred and identify any lessons or improvements we can make to our procedures and processes."

However, the Explosive Ordnance Disposal team had found no explosives at the scene, the spokesperson said.

"Any further inquiries should be directed to the police."