A low-flying plane which appeared to be circling central Auckland with smoke coming from its engines caused panic on Sunday as people feared the aircraft was in trouble.
Eyewitnesses began calling Newshub from around 5pm, describing a low-flying aircraft with smoke coming out of it.
"I saw the plane with smoke pouring out of what appeared to be both engines," an eyewitness told Newshub.
Video taken on a mobile phone shows the aircraft leaving a dark trail in the sky as it passes overhead.
Police confirmed they had been contacted about the aircraft, but neither Airways NZ nor the NZ Defence Force could identify it, with the latter said to 'rule out' the idea that it was a military aircraft.
The plane was finally confirmed as one belonging to Air Chathams, and it wasn't in danger at all.
"It was actually our CEO and Owner Craig Emeny taking Convair ZK-CIB on an approved operational check flight, post a major maintenance check," a spokesperson for the airline said.
The aircraft, built in 1957, is used by the airline on its network, which includes a two hour flight to Norfolk Island.
Earlier in the day, emergency services responded to an Air New Zealand aircraft following reports of smoke in the cabin at Auckland Airport.
That aircraft, which was due to depart for Napier, was deplaned and moved to a hangar to be inspected by maintenance crews.
The passengers were put onto another aircraft and continued their journey to Hawkes Bay.