Thieves stole dozens of boogie boards and used a fire extinguisher to smash a window of a tour bus stuck in sand on Ninety Mile Beach.
The bus was taking tourists sightseeing as part of a tour run by the Fullers GreatSights company and got into trouble while driving along the beach shortly before 11am on Sunday.
Fullers GreatSights Bay of Islands general manager Charles Parker confirmed yesterday the tourists had been transferred to other buses.
It was while the driver of the stranded bus had been away from it, waiting for help to arrive, that it had been targeted.
The bus had not been returned to the Bay of Islands base yet and the damage was being assessed by a contractor in the Far North.
Mr Parker said he was unsure of the total damage and had not yet done an inventory of stolen items.
However, he was aware that at least 31 boogie boards and a first-aid kit had been taken.
"None of the tourists were at risk - they had already gone. The driver left the bus while waiting for the excavators to arrive and that's when it occurred," Mr Parker said.
Heavy machinery from a forestry company working nearby winched the bus free as it was surrounded by the advancing tide. At least 100 tourists had been in a convoy of five buses when one vehicle got stuck in the sand.
Mr Parker said it was not the first time one of GreatSights' buses had become trapped in soft sand at the beach, but it hadn't happened for five years.
"It does happen occasionally. It's just one of the hazards that we undertake when we travel on the beach. The beach changes hourly and so we accept it as a hazard of our operation."
Until he had received a report on the damage and stolen property the incident would not be referred to police.
It was a trip the tourists would never forget and many took photos of the stricken bus as they waited to be transferred to other vehicles, he said.