A catamaran was badly damaged after it ran aground in the Coromandel.
The 40-foot vessel came ashore at Hahei beach.
Witness Graham McKenzie said it seemed the owner drove the boat into the bay and tried to stop 200 metres off shore.
"But the boat was driven directly up on to the beach. He still had the engine running.
"It was quite spectacular."
Mr McKenzie said the owner, a man who looked to be in his 30s, was in a "state of disbelief" immediately after yesterday's incident.
"He didn't know what to do."
The Hahei Fire Service was called to the scene about 8.15pm.
A spokesman said firefighters and surf lifesavers tried to secure the stern of the boat with two anchors to stop it coming further onshore.
Mr McKenzie understood the owner had bought the catamaran only two days before and was on his way to Nelson.
The maritime services team leader of the Waikato Regional Council, Richard Barnett, said the owner of the boat was alone on board at the time.
Mr Barnett said the vessel was badly damaged and the owner's belongings were removed today with the help of the harbourmaster, locals and the council.
"This was done to prevent pollution in the marine reserve as well as lighten the boat," he said.
"One of the hulls has a lot of sand in it so that needs to be emptied out to see the extent of the damage."
The catamaran was pulled up on shore as the tide came in today, and secured with a rope to a bulldozer.
A boatbuilder would assess the damage tomorrow.
Mr Barnett said the initial idea was to refloat the boat and have it towed to a safe spot in Whitianga, but it was too damaged.
The forecast was also for heavy weather, which could have made this more difficult, he said.
Whitianga firm Donovan and Son Contractors was responsible for pulling the vessel on to the shore.
Director Tim Donovan said it took about four hours.
"We're trying to keep it as high up on the beach as we can. Hopefully tomorrow morning we can winch it up the beach and put it on a trailer."