National Australia Bank (NAB) is taking action against organized mortgage fraud following reports of $4 billion in fraudulent loan applications.

The bank identified complex criminal syndicates operating across the real estate, brokerage, and legal sectors. NAB has referred multiple parties to authorities and suspended or removed several individuals and entities from its operations.

Citing a system-wide threat, NAB is calling for a National Economic Crime Strategy to coordinate efforts between banks, regulators, and law enforcement.