The PSNI has received five separate reports of alleged historical abuse at a prestigious Catholic grammar school in Derry dating back over four decades.
Fresh details have emerged after Terry Doran waived his anonymity to reveal details of the abuse he claims to have suffered at the hands of former St Columb's College teacher Raymond Gallagher.
The 59-year-old was paid £50,0000 in 2015 in settlement after taking a case against the college and Gallagher - a former vice-principal at the school.
Gallagher, who died in 2007, was a well-known music and Irish language teacher at the famous college.
According to Mr Doran, Gallagher continued teaching there for years after he made serious sexual abuse allegations in the late 1970s.
It is believed Gallagher left his post at the school in the early 1990s.
In a harrowing story of life-long ill treatment at the hands of the Catholic Church, the 59-year-old has set out in yesterday's Irish News how he was a victim of the cruel mother and baby home system before a church official at St Columb's later rejected his claims of abuse as a teenager.
A police spokesman said that "to date the Police Service of Northern Ireland have received five reports of alleged historical sexual abuse dating back to the 1970/80s.
"In four of these cases all lines of enquiries have been exhausted."
Margaret McGuckin from the campaign group Survivors and Victims of Institutional Abuse (SAVIA) last night said the Catholic Church and St Columb's College need to reveal what they know.
"What I would like them to do is delve into their records about those who spoke up about their abuse and were told 'that's nonsense'.
"That's essentially what's they said to young Terry Doran."
Fresh details have also emerged today about how Gallagher groomed children at the college.
Former pupils spoken to by the Irish News said that Gallagher was a regular visitor to the school's changing rooms during PE and that he would routinely watch boys showering.
One man who did not want to be named, said the former teacher would often ask boys to return to the shower block saying they had not washed themselves properly.
He said by the time they would re-emerge the shower area the changing rooms would be empty.
"He was a predator," the man said.
"Everybody knew and nobody did anything," he said
St Columb's College was contacted.