A tug boat packed with pleasure seekers collided with the Queen Elizabeth cruise liner during CentrePort's open day.
CentrePort has begun an internal investigation and notified Maritime NZ of the accident, which happened about 3pm on Saturday.
The tug master in charge of the Toia tug was presently on rostered days off, marine services manager and chief pilot Charles Smith said.
He would not say whether the "very experienced" tug master had been stood down, however, The Dominion Post understands that would be the usual procedure after such an incident.
Mr Smith said nobody was injured in the incident but the Toia was filled to capacity with 50 people on board.
The accident happened as the Toia was motoring up the port side of the Queen Elizabeth.
The tug's funnel hit the ship's docking platform, which was about 12m above the water line.
The Toia's funnel was damaged, but it had remained in service.
Passenger Murray Holden said debris showered the tug's passengers when the collision happened.
Passengers screamed as rusted metal from the funnel rained down, cutting Mr Holden's cheek.
"It was extremely lucky that no one appeared to be seriously injured, as there was debris all around us . . .
"Just why the Toia tug master was so close to the Queen Elizabeth [is unclear]. I can only assume he wanted to give the passengers a thrill and we certainly got that and more."
A Maritime NZ spokesman said "preliminary inquiries" were under way, which should take about two days.
There was slight damage to the cruise ship's platform, "but nothing to impede or significantly delay departure that evening".
It was unusual for the tug to be so close to the cruise ship, he said.
Cruise New Zealand chairman Craig Harris, agent for the Queen Elizabeth, said under usual circumstances in a collision ship owner Cunard would "note protest" with the port about the incident while awaiting an investigation.
There were hundreds of similar incidents each year, he said. "This was unusual because the ship was sitting alongside [the wharf] and the bloody thing hit it."
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