Media playback is unsupported on your device Media caption Father Francis Davidson resigned from his current post following an investigation into abuse at the school where he had been a headmaster

A former headmaster of a scandal-hit Catholic boarding school has resigned from a senior role at a Benedictine college of Oxford University.

Father Francis Davidson is accused of covering up child sex abuse during his time at Fort Augustus Abbey School in the Highlands.

He is quitting as monastic superior of St Benet's Hall.

He was responsible at the Oxford college for the welfare of student monks.

Fr Davidson's resignation follows a BBC Scotland investigation into physical and sexual abuse at Fort Augustus and its preparatory school in East Lothian, Carlekemp.

Since the programme was broadcast on 29 July at least 30 more ex-pupils have come forward alleging abuse at the schools between the 1950s and 1990s.

It brings to about 50 the total number of alleged victims who have spoken to the BBC.

In total, 10 monks are now accused of physical abuse; four monks and one lay teacher of sexual abuse including rape; and three headmasters of cover-ups.

'Cover up'

One of those involved was Fr Chrysostom Alexander, confronted by the BBC in Sydney last month over allegations he molested a 14 year old pupil and that it was covered up by Fr Francis Davidson.

A second alleged victim of Fr Chrysostom has come forward, and told how he had tried to raise the alarm with Fr Davidson.

Hugh Kennedy attended the school in the 1970s. He says he was groomed and sexually abused by two teachers, including Fr Chrysostom.

Mr Kennedy, 50, said: "He would play with me, masturbate me and would make me do certain things to him, oral sex, things along those lines.

Media playback is unsupported on your device Media caption Hugh Kennedy says he was groomed and sexually abused by two teachers at the school in the 1970s

"I did tell Fr Davidson, who was the headmaster."

Mr Kennedy said that the police were never involved, and Fr Chrysostom was allowed to travel to Mr Kennedy's home to protest his innocence to his family.

He said: "Chrysostom spent an hour with my stepmother. I assumed this was to discuss the abuse or the allegations I'd made and I wasn't party to that conversation.

"Suffice to say when Chrysostom came out from having talked to my stepmother the look on his face will live with me forever because he knew he had convinced her this was a non story and that from there I was sent back to Fort Augustus to be subjected to further abuse by Chrysostom."

Lay teacher

Mr Kennedy says he was also abused during the same period by another man, a lay teacher at the school called Bill Owen, fuelling fears that abusive staff were sharing victims.

Mr Kennedy's claims come two weeks after a BBC Scotland Investigates programme Sins of our Fathers alleged that the school had failed to alert police to another allegation of abuse from a second boy in 1977, choosing instead to send Fr Chrysostom back to his native Australia.

The victims are clearly very concerned that there was a lot of information they're saying the church had that they haven't acted on and the issue of trust is massive Anne Houston, Children 1st

Two days ago the BBC asked Fr Davidson, the only surviving headmaster for his response to new evidence that he and others had covered up abuse by Father Chrysostom Alexander in the 1970s.

Today, he provided a statement to the BBC: "Once again, I would like to offer my profound sympathies to former pupils of Fort Augustus Abbey School and their families for any historic abuse committed by Fr Chrysostom Alexander, including to Hugh Kennedy.

"I was shocked and saddened to hear of Mr Kennedy's allegations and of those against Bill Owen relating to Fort Augustus in the 1970s. I do not recall them being reported to me during my time as headmaster of Fort Augustus Abbey School.

"Subsequent allegations of abuse made to the Abbot, who is now dead, resulted in an internal investigation by the Abbot and Fr Chrysostom's immediate removal from the school.

"Today's requirements for child protection are rightly far more comprehensive than those in place when I was a headmaster.

"As investigations into matters at Fort Augustus Abbey School and Carlekemp Priory School are ongoing, I have stepped aside from my role as religious superior at St. Benet's Hall."

The leading children's charity, NSPCC, is now calling for a full independent inquiry into the abuse at the school.

Peter Watt of the NSPCC said: "What's absolutely clear from the film is that the Catholic Church cannot investigate itself.

'Hugely important'

"What the film showed powerfully is over decades the Catholic Church appeared to be more interested in protecting its own reputation than protecting the interests of the children it was supposed to be caring for.

"And therefore I think there should be an independent inquiry and that should start as soon as possible so that those victims who have already spoken, and those who may consider speaking, will have the confidence that they will be listened to, and listened to seriously."

Children 1st chief executive Anne Houston told the BBC's Good Morning Scotland programme that she supported calls for a full independent inquiry.

"There's an ongoing police investigation which we're very supportive of…but we're very aware that for a number of the men the people they are accusing are dead," she said.

"However it is hugely important for victims of physical and sexual abuse to have their experiences when they were children acknowledged, for that to be open and they are clearly very concerned that there was a lot of information they're saying the church had that they haven't acted on and the issue of trust is massive.

"Its unacceptable for an internal inquiry. They (the Catholic Church) must open their doors and they must pass on any and all information they've had both to the police investigation but also to someone who's independent who can set up that kind of inquiry.

"The trust is lost. It's hugely important for the victims."

Police have confirmed they are investigating the allegations.

Two weeks ago the Bishop of Aberdeen, Hugh Gilbert, apologised on behalf of the Catholic church in Scotland, calling the abuse "bitter, shaming and distressing".

Carlekemp closed in 1977 and Fort Augustus Abbey School was shut in 1993.

BBC Scotland Investigates: Sins of Our Fathers will be broadcast again on BBC2 on Monday 19 July at 23:20, and for a week afterwards on the BBC iPlayer