A former childcare worker has been charged with 1,623 child abuse offenses allegedly carried out against 91 children in Australia and elsewhere over 15 years, the Australian Federal Police (AFP) said in a statement on Tuesday.

The 45-year-old man from the Gold Coast has been in police custody since August 2022, when he was initially charged with making child exploitation material and using a carriage service to distribute it.

Police said a special investigation uncovered more child abuse material on electronic devices allegedly owned by the man, who worked in a dozen childcare centers in Brisbane, Sydney and an unspecified location overseas between 2007 and 2022.

“This is one of the most horrific cases of alleged child abuse our detectives have seen,” Assistant Commissioner Michael Fitzgerald with the New South Wales police said in a news conference.

Other charges include hundreds of counts of indecent treatment of a child under 16 years, counts of making child exploitation material and other charges related to possessing, producing, distributing or obtaining child exploitation material.

Police said all the children allegedly offended against were pre-pubescent girls and that they were “highly-confident” that all 87 Australian children recorded in the alleged material had been identified and their parents informed of the investigation.