She says AUT can't comment any further because of the police inquiry.
Over $500,000 missing
AUT has been making an urgent audit into the suspected theft but would not reveal any details, including whether a staff member was responsible, how long the alleged offending remained undetected or how it was discovered.
"There is a matter under investigation into possible accounting discrepancies. As this is under investigation we cannot comment further," said an AUT spokeswoman.
The head of the Auckland fraud squad, Detective Senior Sergeant Hywel Jones, said a complaint had been laid on Monday, but would not comment further.
Unravelling employee theft and fraud is 70 per cent of the workload for private investigator Danny Toresen.
While not commenting specifically on the AUT case, Mr Toresen said most employee thefts or frauds were picked up by tip-offs from colleagues, rather than through audits or controls.
"The more senior the manager, the larger the scale of the fraud," he said.
"The most common ways to commit fraud is to reactivate old creditors and account numbers, then siphon the money off.
"Fraud can be easy to unravel once detected ... But these long-running frauds can be millions of dollars if they know how to avoid being picked up."
The largest employee theft committed in New Zealand was by former ASB investment banker Stephen Versalko, who stole $17.8 million over nine years.
He was sentenced in March last year to six years in prison.