Police investigating alleged historical sexual offending at Dilworth School have made an additional arrest today.

A 60-year-old man has been charged in relation to sexual violation, attempted sexual violation, indecency and indecent assault.

Detective Senior Sergeant Geoff Baber said police have continued to receive dozens of calls since yesterday.

"Over the past 24 hours, the Operation Beverly team has received more than 50 calls and emails from members of the public."

Baber said police are now assessing this information and will be making follow up enquiries on any relevant matters.

"Police recognise that it can be difficult for victims to come forward. We respect the courage of those who have contacted us."

"We continue to encourage anyone who may have information that can assist our investigation to come forward."

Yesterday, police announced six men, who are all in their 60s and 70s, had been charged in relation to alleged sexual offending.

The men appeared in the Auckland District Court and were granted name suppression.

They are expected to appear again in the same court in early October.

When the news broke yesterday, school management held a press conference to publicly address the situation.

Headmaster Dan Reddiex, who was appointed last year, said that "naturally as a father, educator and human being" he found the allegations "appalling" and "deeply saddening".

"I cannot comprehend the trauma or pain those who suffered abuse must have endured," Reddiex said.

"And for this hurt we are truly sorry. And so I want to be absolutely clear, the Dilworth School I know and lead today has zero tolerance for abuse of any kind.

"The health, safety and wellbeing of our students is our single greatest priority and responsibility.

"We know that a safe environment is instrumental to our students flourishing both personally and academically."