A shocking new report has identified hundreds of victims of child sex abuse by Irish Catholic priests, officials and clerics say, two months after a landmark study found "endemic" mistreatment.

A government-appointed commission of investigation headed by a judge has been probing allegations of abuse by priests in the archdiocese of Dublin - the country's biggest - since March 2006.

Archbishop of Dublin Diarmuid Martin has warned that the report - being presented to Justice Minister Dermot Ahern on Tuesday - would "shock us all".

It is the first time the state has investigated how the once-powerful Church in mainly Catholic Ireland has run its affairs.

It probed whether the Church reported abuse allegations or attempted to "obstruct, prevent or interfere with the proper investigation" of complaints.