In a statement provided to The Standard, the victims said they had “grave concerns” about the way the Missionaries of the Sacred Heart (MSH) managed the allegations when they were reported by students, all aged under 16 at the time.

They also had “grave concerns” about the way the MSH managed Mamo during the time the sexual offences occurred at the Hamilton school.

“We also have serious questions that we would like the Missionaries of the Sacred Heart to answer, relating to their duty of care to us while we were under their care as young boys,” the statement added.

They have now engaged Melbourne lawyer Dr Vivian Waller to fully investigate their concerns.

Mamo, 68, pleaded guilty in the Warrnambool County Court this week to seven charges of unlawful and indecent assault of a child under the age of 16. The victims told of being taken into a dark basement at the college and indecently assaulted between 1976 and 1980.

Mamo will be sentenced in a Melbourne court next February.

“Although it has taken 30 years, this is a victory not only for us as survivors, but represents a victory for all who have suffered sexual abuse,” the victims said.

The head of Monivae College yesterday apologised unreservedly to the students who were abused by Mamo while he was based at the school.

Principal Mark McGinnity confirmed that the MSH brother was a staff member at the Hamilton school from the late 1970s until 1980.

While he did not teach, he lived on site and worked as a bus driver, hockey coach, groundsman and laundry employee.

Mr McGinnity said he first became aware of the allegations surrounding Mamo earlier this year when police visited the school and made inquiries.

He said both he and the MSH had assisted police fully with their investigations.

Monivae is still linked with the MSH, although there is just one priest who is the sole representative of the order at the college.