A bag with NZ$1 million ($667,000) went missing after it fell while being moved at Hong Kong International Airport.

The bag was one of 13, holding a total NZ$10 million, being sent to the Bank of China in Hong Kong from New Zealand, Chinese media said.

Three bags reportedly fell off after being unloaded from a Cathay Pacific flight on July 17. Airport staff who went to retrieve them found only two.

The airline said police were investigating.

Reports in China said surveillance footage broadcast in China showed the three unfastened bags falling from a trailer as it turned a corner.

When staff realized the bags were missing 10 minutes later, they returned, the website said.

Chinese media said police were treating the disappearance of the bag as theft.

A statement by the airline said: “Cathay Pacific transported a valuable cargo shipment last Friday night to Hong Kong.

“Upon arrival, it was transferred to the cargo terminal where part of the shipment was found missing. As the case is under police investigation, we are unable to provide further details.”

G4S International Logistics, that was transporting the money to the Bank of China, said the money was safe until it entered the controlled airside section of the airport – a section to which their staff have no access.

The money was insured, the company said.