An ex-Catholic priest living in Asia who was nicknamed "the Phantom Feeler" by boys at a leading Wellington Catholic school is being investigated by police.
A man who says he witnessed the priest groping boys in the 1970s said the Church and school must do more to uncover the extent of Father AM Donnelly's crimes.
Police recently interviewed two men in their 50s who said they saw the dormitory master groping a boy under the sheets one night in a dorm at St Patrick's College, Silverstream, in 1974.
One of the men who agreed to speak on condition of anonymity said the abuse was no secret.
He said after one assault a poster was put up on the school noticeboard, which stated "the phantom feeler strikes again".
"All the children knew who the phantom feeler was and we knew about his antics," the man said.
"Most of the people at the school saw it before it was pulled down, but it probably brought a lot of this matter to the attention of the powers-that-be."
He knew of three victims of Father Donnelly and said there had to be many more.
One of three he saw being abused denied anything had happened in the days after the assault.
The Society of Mary has now revealed it upheld two complaints, laid in 2002 and 2005, against Father Donnelly, involving sexual abuse of St Pat's boarders under the age of 16 during the early 1970s.
It offered the men help and informed them they could go to the police, the religious order told RNZ in a series of statements.
The Society of Mary, also called the Marist Fathers, runs eight secondary schools in New Zealand.
Police have refused to say why the case was being investigated now.
It was investigated at the time by the school, the Society said.
"Boys indicated to the acting principal at the time that someone was in their dormitory at night, it was dark, and they thought it might be Donnelly.
"We are not aware that there was ever a specific complainant, or whether it was said by someone on behalf of someone else," the Society statement said.
"The acting principal investigated the matter, and Donnelly vigourously denied it."
St Pat's said it had no record of this investigation, or of any abuse by any staff against boys at any time over the years.
However, it is now known that boys were abused at the school across at least three decades, and in each case the students formed nicknames for the abusers. They called 1950s rector Fred Durning 'Fred the Fiddler' and in the 1980s, Alan Woodcock was called 'Penis Radiata'.
It was usual for schools not to hold records going back so far, the Society said.
The witness said they shared the blame.
"The offender was, I believe, a sick man whilst the people who knew about it and had the ability to stop this, they were not sick people and they made a conscious effort trying to deny it or make it go away or hiding it," he said.
"I find them equally as responsible as the offender."
The Marist Fathers refused to say where they sent Father Donnelly after St Pat's, though it was probably to one of its schools in Hawke's Bay.
They would not say where else he taught, claiming that the release of such a record could unfairly harm a school and students today. The order aid its media protocol was not to name such schools.
"While we are prepared to give appropriate information (taking into account legal and privacy issues) it is important to record that people have come to us after the publication of these stories saying that they have felt re-traumatised and re-victimised.
"It is also important to ask if publishing this information might prejudice a possible police investigation ... a complainant could still take this to police given that Donnelly is not dead."
The witness rejected the order's position and said it was a sign it was unwilling to confront the abuse.
"There may be many victims who may feel a bit more empowered knowing they're not the only ones," he said.
Father Donnelly taught at St Pat's from 1968 to 1974.
The Society said he left to work in Asia in 1979 and while there left the priesthood, married and had a child.
It said it did not know where he was located now.