Nine alleged victims have made complaints against a former GAA official accused of sexual abuse and voyeurism offences over a 30-year period, the High Court has heard.
Prosecutors also claimed Thomas McKenna, 58, had stored more than 50,000 photos and video clips – many depicting young men and boys naked or partially clothed.
Police are still trying to establish the identities of some of those in the images, a judge was told.
Details emerged as the former club treasurer for Crossmaglen Rangers was refused bail.
Mr Justice McAlinden said: “The allegations made against the applicant are of the most horrendous nature in terms of offending against young vulnerable children.”
McKenna, of Woodside Park in Bessbrook, Co Armagh, faces a total of 17 charges which cover a period between 1988 and his initial arrest in August this year.
They include two counts of buggery against persons aged over 16 without consent, and two gross indecency offences, one of which was against a child.
He is also charged with sexual assault, voyeurism and eight counts of indecent assault, along with making and possessing indecent photographs of children.
The retired postman is further alleged to have interfered with mail during his time of employment.
Crown lawyer Kate McKay said the charges relate to a “serious and complex investigation” into claims of historical sexual offences.
“It involves, to date, nine injured parties,” she told the court.
Those complainants have come forward to speak to police and provided interviews about alleged incidents.
Mrs McKay set out how they also claim McKenna took photos and videos of them at locations without their permission.
Police searches led to the recovery of devices said to contain 43,000 still images and 8,000 short video clips – some allegedly taken covertly.
According to the prosecution the haul included photos taken in recent times.
Opposing bail due to the risk of reoffending, Mrs McKay revealed that a threat message has been served on McKenna.
Kevin Magill, defending, responded that his client was merely advised of heightened tensions in Crossmaglen.
He said the accused served as treasurer for Crossmaglen Rangers for many years.
The club has issued a statement in which it assured members of its “robust child safeguarding procedures”, encouraged anyone with information in relation to the investigation to co-operate with the authorities, and confirmed the former officer has been excluded from all activities pending the outcome of police inquiries.
Ruling that McKenna must remain in custody, Mr Justice McAlinden pointed out that not all the alleged offences are historic.
He said: “The court would be remiss in its duty to protect the public if bail was granted in this case.”