(CNN) -- Police are investigating accusations that the former archbishop of Belgium knew of sexual abuse in the church but failed to stop it, the Belgian prosecutor's office told CNN Tuesday.
Cardinal Godfried Danneels was archbishop of Belgium for more than 30 years before he stepped down in January.
Belgian police raided the national headquarters of the Catholic Church last month over allegations of child abuse, prompting an angry response from Pope Benedict XVI and other church leaders.
Investigators seized archdiocese archives covering 25 years as well as personal computers and other personal possessions, said Fernand Keuleneer, a lawyer for the archdiocese.
Police raided the private residence of Danneels and the headquarters of the Catholic Church in Belgium, where a meeting of bishops happened to be taking place.
They detained the bishops and other church employees -- even the cook -- for about nine hours, De Beukelaer said. Investigators also seized personal possessions and have not yet returned them, he said.
Members of a Belgian church commission that helps sexual abuse victims resigned en masse to protest the raid a week after it took place, a spokesman for the Mechelen-Brussels Archdiocese said.
The commission worked with people who have been abused by clergy members, said the spokesman, the Rev. Eric De Beukelaer.
The Belgian Prosecutor's Office said Monday it is investigating death threats against witnesses and magistrates involved in clergy child abuse cases.
The Vatican criticized the raids but reaffirmed its "strong condemnation of any sinful and criminal abuse of minors by members of the church." It cited "the need to repair and confront such acts in conformity with the law and teachings of the Gospels."
The Catholic Church is facing allegations that clergy members abused children in at least half a dozen countries, including the pope's native Germany, as well as Belgium, Ireland, Austria, the Netherlands and the United States.
CNN's Lianne Turner contributed to this report.