Pope Benedict has joined mounting Vatican criticism of raids by Belgian police investigating alleged child sex abuse, calling them "deplorable".
In a message to Belgian bishops, the pope expressed his solidarity "in this moment of sadness".
Several buildings were searched in raids targeting a retired archbishop and the graves of two prelates.
Prosecutors said the action concerned alleged "abuse of minors committed by a certain number of Church figures".
Police in Leuven, central Belgium, on Thursday seized nearly 500 files and a computer from the offices of a Church commission investigating allegations of sex abuse.
They also searched the Church's headquarters and the Brussels archdiocese in Mechelen, north of the Belgian capital.
Belgium's bishops, who were holding a meeting at the time of the raids, were kept incommunicado for nine hours while the searches were conducted.
'Unprecedented treatment'
Pope Benedict's criticism of the raids came in a message of support to Brussels Archbishop
Andre Joseph Leonard, the head of the Belgian bishops' conference.
"I want to express, dear brother in the Episcopate, as well as to all the Bishops of Belgium, my closeness and solidarity in this moment of sadness, in which, with certain surprising and deplorable methods, searches were carried out."
"I hope that justice will follow its course while guaranteeing the rights of individuals and institutions, respecting the rights of victims, (and) acknowledging those who undertake to collaborate with it," Pope Benedict said.
On Saturday Vatican officials compared the raids and investigation into allegations of child sex abuse with the treatment of the Church under communist rule.
Cardinal Tarcisio Bertone, the Vatican Secretary of State, described the detention of priests "serious and unbelievable".
"There are no precedents, not even under the old communist regimes," he said.
The Vatican has summoned the Belgian ambassador to the Holy See to voice its anger at the incident.
The Catholic Church in Belgium has apologised for its silence on abuse cases in the past.
The church was rocked in April when the bishop of Bruges, Roger Vangheluwe, resigned and admitted to sexual abuse before and after becoming a bishop.
