The organisation that administers the Waitangi Treaty Grounds says the Serious Fraud Office is looking into "financial irregularities".
Dennis McBrearty, acting chairman of the Waitangi National Trust Board, says a probe was launched "as soon as the irregularity was discovered".
McBrearty told the Herald the irregularities related to transactions over a 12 month period beginning in 2016, and had been picked up by staff during routine analysis of accounts.
The Serious Fraud Office is tasked with investigating and prosecuting serious financial crime, typically frauds exceeding $5 million or with significant public interest.
McBrearty confirmed the irregularities fell below the $5m threshold, but said "specialist advice" sought by the board had recommended a SFO referral given the "public nature" of the trust board.