ROME — A letter sent to Pope Francis has triggered Spain’s largest clerical sex abuse scandal to date, leading to charges being filed against 10 priests after a college professor wrote to the pontiff to describe sexual abuse he claims to have suffered as a child.

Upon receiving the letter, Francis reportedly telephoned the victim on Aug. 10. In Spanish media accounts, the victim is identified as “Daniel”; his real name has been withheld for privacy reasons.

In the victim’s Aug. 10 conversation with Francis, according to media reports, the pontiff apologized in the name of the Church for the abuse he suffered and encouraged the victim to file civil charges against the priests who he said abused him.

According to Spanish reports, a subsequent police investigation uncovered a criminal network of pedophiles that involves at least 12 people among priests and laity from different parishes in the Spanish city of Granada.

Investigators say the total number of victims of this network is currently unknown. It’s also not clear if people outside the Catholic Church may have been involved.

During a press conference Tuesday in Granada, a government official named Santiago Pérez said officials are investigating whether the sexual abuse “can be attributed exclusively to religious people or if there are others involved, either because they were affected [by the crimes] or that might have otherwise been complicit [with the criminals].”

According to a statement published on the diocesan website in Granada, the allegations were investigated and, after being considered credible, the priests were removed from ministry.

“The whole body of the Church hurts immensely by the fact that scandals of this nature occur,” the statement said. “The veracity and scope will have to be determined by the judicial authority through the already opened investigation.”

On Monday, Archbishop Ricardo Blazquez of Valladolid, president of the Spanish Bishops Conference, expressed the local Church’s willingness to collaborate with judicial authorities, the Pope, and the Vatican’s Congregation for the Doctrine of the Faith.

Although Francis’ response to clerical sexual abuse at times has been considered slow, Vatican spokesman are characterizing his personal involvement in this scandal as a sign of his commitment to guaranteeing zero tolerance for these crimes.

Since he was elected pope in March 2013, the Argentine pontiff has created a papal commission for the protection of minors that is set to lead the reform on clerical sex abuse, welcomed six victims of pedophile priests to the Vatican, and launched a criminal procedure against a defrocked archbishop and papal diplomat accused of paying underage boys for sexual acts in the Dominican Republic.

The pope also authorized an investigation of Bishop Robert Finn in Kansas City-St. Joseph, to date the lone American bishop to be criminally convicted of failure to report child abuse.