Residents in Lower Hutt were spooked on Wednesday night as helicopters buzzed over the suburbs with no lights and no record of their presence on flight tracking websites.
Social media community pages blew up with people reporting seeing the helicopters with no lights along with a line of blue lights.
A search of flight tracking websites left residents further confused with no flight data showing, despite the air traffic.
Police confirmed they and the Airforce had been doing some joint training exercises for Search and Rescue in recent days, but the public was not notified.
Sonya McIntyre saw a similar exercise between Petone and Lowry Bay on Monday.
An image of a helicopter a resident saw flying over Lower Hutt. Photo: SUPPLIED
McIntyre observed the helicopter hovering over the water for about an hour, doing the occasional loop.
A police spokesperson said these types of exercises were typically posted on the police Facebook pages, but on this particular occasion that did not happen.
The spokesperson said police would try to advise the public next time.
An NZDF spokesperson confirmed two of their helicopters were working with police in a tactical training exercise in the area on Wednesday night.
"The exercise was run in consultation with the Greater Wellington Regional Council. These exercises are run routinely at various locations throughout New Zealand to ensure the NZDF and police are trained and prepared to respond to a range of situations."
The aircraft did not always appear on civilian flight trackers, but there was no impact on safety as they were visible to air traffic control, the spokesperson said
The training exercise is finished.
"The NZDF attempts to have the least impact on the public as possible during these activities.
"We acknowledge that these types of training exercises could not happen without the support of our local communities."
One complaint was received by the Civil Aviation Authority (CAA) and it was in relation to noise made by a helicopter in Lower Hutt on 12 February, a spokesperson confirmed.
"The complainant has been advised that CAA only has authority over noise abatement with regard to requirements at some major airports, and therefore there is no further action that the CAA can take."
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