Now, police suspect dozens of those boys were abused during hypnotic ''prayer'' sessions.

The top NSW boarding school, in central west NSW, is reeling after 13 former students alleged sexual abuse by staff during the 1970s and early 1980s.

The 65-year-old former priest faces 33 charges after allegations a paedophile ring of priests and staff operated at the school, which has boarders and day students.

He was charged on May 23 with offences relating to sexual assault and gross acts of indecency of boys aged between 10 and 18.

One alleged victim, who finished Year 7 at the college in 1986 before he was expelled, blew the whistle on Spillane's alleged sex offences.

The shocking revelations yesterday prompted one former student to tell his story of abuse at the school in 1971, for which he eventually received an out-of-court settlement.

The man, who asked only to be known as John, said he was sexually abused three times in April 1971.

''I still remember it,'' John said yesterday .

''I carry that stench on my back ever since the day it happened.

''I was a day boy and I was not the only victim back then.''

In the mid-1990s, he contacted the Vincentian order of priests, which run the school and operate separately from the Bathurst Catholic diocese.

He eventually settled out of court for just over $40,000.

He said criminal proceedings against the priest never went past the committal hearing because of lack of evidence.

Currently, 615 boys attend St Stanislaus, of which 188 are borders.

St Stanislaus's principal John Edwards said he first became aware of the allegations ''several years ago'' and referred the claims to police.

''The college received some internet material which contained allegations that I think are linked to the ones that are currently taking place,'' he said yesterday.

''Those matters were referred to the police some years ago.''

He said the material included claims of late night prayer and chanting sessions in which boys were sexually abused.

Police have issued scant information but urge other victims of alleged abuse to contact them.

Detective Superintendent Michael Goodwin would not reveal how many suspects were being investigated, but said none still worked at the school. ''I can confirm that there's no one at the school at the moment that is subject to that inquiry. At this stage, we're looking at 13 victims and we're following up those lines of inquiry at the moment.''

A spokeswoman for the Bathurst diocese would not comment, saying the Vincentian priests operated separately from the diocese.

A spokesman for the Sydney archdiocese said Cardinal George Pell would not comment because Bathurst lay outside his jurisdiction.

Chairman of the National Council of Priests of Australia, Father Ian McGinnity, said care was taken at boarding schools, but sex abuse remained in all parts of society.

''It still doesn't take away the unfortunate reality of human nature. There are people who sometimes have sicknesses in psycho-sexual arenas and that happens whether they're priests or lay people.''

The office of Vincentian priests at Bathurst and their provincial office in Sydney did not comment when contacted. AAP