A metal object struck by a couple digging out their back garden recently later turned out to be a four-tonne army tank.
Jane and Emanuel Hurley discovered the World War 2 bren-gun carrier on their Ohaupo property, 17km south of Hamilton.
A few weeks ago, Mr Hurley was rotary hoeing the garden when he struck metal.
"He started uncovering it, thinking he could pull whatever it was out, but he had no luck," said Mrs Hurley.
A neighbour who owned contracting machinery also had no joy so they all took a break for a day or so.
"Then a friend made it his mission to uncover whatever it was," said Mrs Hurley.
"He had a go at it every day or so and slowly exposed it."
When they realised the enormity of what they had found, they called in a scrap dealer who had to use two trucks for two hours to haul out the mystery object.
Mrs Hurley said they realised it was some kind of military vehicle.
She took photographs and was editing them on the computer in their antique shop Collectamania when a customer identified it as a bren-gun carrier. More checking confirmed its identity.
Mr Hurley said the carrier was beyond repair.
Mrs Hurley had heard some former military vehicles were used on farms after the war.
"The things you find in your garden," she said.
Not only that, but they now have a huge hole to fill.
"Who knows, we might even put a swimming pool in.".