Two more sex offenders have had ties with Caldey Island which is at the centre of calls for an inquiry into historical abuse, a source has claimed.
Six women have been paid compensation following sexual abuse by a monk at the Pembrokeshire island's abbey.
It later emerged a fugitive child sex offender fled to the abbey to hide out.
The abbey has confirmed a priest was convicted of offences after leaving the island but denied knowing a serial sex offender had also stayed on the island.
BBC Wales has reported in recent weeks that Father Thaddeus Kotik lived on the island for 45 years and abused several girls there in the 1970s and 80s.
Child sex offender Paul Ashton fled to Caldey island in 2004 while on the run from the police after being charged with possessing indecent images of children.
He lived in the abbey until he was arrested in 2011.
Another sex offender believed to have lived on the island is notorious predator John Cronin.
740 indecent images
The other, Rev John Shannon, was Caldey Island's parish priest at St David's Church in 2008. He was later jailed for possessing indecent images of children, having left the island.
Psychiatrists labelled Cronin one of the most dangerous sexual predators in Britain after he committed 50 offences including an attack on a woman in 1992 in which he posed as a priest.
Shannon admitted downloading 740 indecent images of children and was jailed for eight months in 2011.
The abbot, Father Daniel van Santvoort, said that Shannon took on the role of priest on a trial basis with the abbey's approval after islanders asked for the parish church to be reopened.
He said he "came with good references and took up residence in a cottage" but the role of a parish priest was "not viable" and he left the island within nine months of his arrival in 2009.
"We understand that some time later, whilst working on the mainland elsewhere in the UK, he was investigated by the police for offences committed on the mainland after he had left the island and was subsequently convicted," said Father Daniel.
"That inquiry did not involve any allegations of offences committed on the island and the police did not conduct any inquiries on the island in respect of this person.
"We understand, therefore, that he had no criminal convictions when he came to the island nor when he left."
Kotik's victims have echoed calls by the Welsh Conservatives for an inquiry to be set up.
The source, who does not want to be publicly identified, said Cronin stayed on the island for a month under an alias, at the same time that Ashton was living in the tower at Caldey Abbey, but left in 2009.
Father Daniel said the abbey did not know of Cronin's alleged stay.
"We have no knowledge of this person whatsoever. The name is completely unfamiliar to us," he said.
The source said: "I hope that an inquiry will be opened into this island."
The Welsh Government has ruled out an independent inquiry as Dyfed-Powys Police is investigating.