Auckland International Airport has sacked an employee and called in police after finding more than a million dollars has been spent in unexplained transactions.

In an announcement late yesterday afternoon the Airport said the "non-executive employee" was also being pursued through the courts over the transactions which added up to at least $1.84 million.

The revelation marks the third high-profile case of alleged financial misappropriation to hit large listed companies following earlier cases at SkyCity Entertainment Group and Mighty River Power.

Phil Neutz, the Airports' chief financial officer, said in the statement the company's auditors EY had been tasked with probing the matter and their investigation was still ongoing.


"It is important for investors to note that while this is a very serious matter, the sum of money involved does not impact our current financial statements or previous reported results," he said.

Neutz said he was unable to comment further due to the ongoing legal action and police investigation, and an airport spokesman said he could not comment on when its civil action would come to court or whether freezing orders had been sought or granted against the former employee. EYs senior manager of fraud investigations, Logan Nicholls, was similarly non-communicative.

The disclosure of the missing funds and complaints of criminality come just ahead of the Airports' long-scheduled presentation of annual financial results on Friday.

Market analysts are picking the result for the 2015 financial year to be positive, with Morningstar suggesting ongoing growth in tourism would see revenues this year exceed $500m and profits to tipped to be $328m.

The Airport case comes after two other former employees of large listed companies find themselves facing court action this week over claims they misappropriate millions of dollars of employers' money.

Paul Kenneth Rose, a former electrical engineer at Mighty River Power, is currently on trial at the High Court at Auckland facing four charges of obtaining $2.3m by deception.

The offending allegedly took place over his eight years of employment at the power generation which only ending after he was dismissed following an investigation in December 2012.

Rose has pleaded not guilty to charges he abused his position by buying and marking-up parts and equipment he would then on-sell to Mighty River Power.

SkyCity is chasing Tessa Grant through the High Court for $1.27m after uncovering alleged fraud.

The casino operator reviewed Grant's activities as a senior manager at its Hamilton casino between 2006 and 2014, after she pleaded guilty last year to defrauding Waikato Diocesan School for Girl of almost $800,000.

Danny Toresen, a director of private investigation firm Thompson and Toresen, said employee theft was a constant source of business for his firm, and a constant scourge for his clients.

"It can be any industry, from small family-owned to big public companies. Most businesses put trust into people and there's always a certain percentage of the population who will abuse that trust," he said.

Toresen said referring matters to Police often only came at the end of the investigation process, which earlier concentrated on attempting to recover funds.

"Once it's with the Police it's out of everyone's hands. They're understaffed, and only interested in a quick conviction and digging down. All they want is a quick case, delivered on a plate."

Toresen said the three cases of alleged fraud by employees of listed companies was likely only "the tip of the iceberg".