Leon, Mexico (CNN) -- On the same day Pope Benedict addressed and blessed a group of 1,800 children in Guanajuato, Mexico, three Mexican authors released a book accusing the Vatican of hiding or ignoring cases of child sex abuse by Roman Catholic priests.
The book, "La Voluntad de no Saber" (Willing Not to be Aware), chronicles multiple cases of sexual abuse of minors committed by Marcial Maciel, a Mexican-born Roman Catholic priest who was influential at the Vatican.
Maciel, who died in January 2008 at age 87, was the founder and director of the Legion of Christ and the Regnum Christi movement.
The book was authored by Jose Barba, a former seminarian who says he was the victim of sexual abuse by a priest. Historian Fernando M. Gonzalez, a co-author, says the book is based on 212 documents leaked from the Vatican.
Alberto Athie, a former Catholic priest and whistle-blower, also contributed to the book.
According to the book, the Vatican had knowledge of multiple cases of sexual abuse committed by Maciel decades ago, but church authorities chose to do nothing about it.
Pope Benedict removed Maciel from active ministry in 2006 as a result of an investigation launched by his predecessor, Pope John Paul II.
Athie said the church either ignored or archived for years allegations of child sex abuse when he reported them during his years as a priest.
"How could this have been possible?" Athie said. "How can one explain it? I had to face a reality that I never imagined, that I never expected and I never looked for."
Gonzalez said the Vatican documents provide solid proof of a policy geared towards hiding cases of abuse.
"Anybody would have been able to perfectly learn about it by simply asking for the dossier (of sexual abuses cases). Be it John Paul II, Paul VI, John XXIII, any of them should have figured out that a series of denunciations was being hidden, euphemized, protected, delayed, silenced and distorted," he said.
Speaking to reporters Saturday, Cardinal Jose Francisco Robles, head of the Archdiocese of Guadalajara, defended the pope and the church.
"If there has ever been a pope who has faced (the sexual abuse problem) with realism and energy that's Pope Benedict," he said. "Nobody can accuse him of being complicit or lacking will."
Pope Benedict has not specifically addressed the accusations, but in his message to the children at Plaza de la Paz, or Peace Square, in the colonial city of Guanajuato, he spoke about the church's role in protecting children.
"I raise my voice," the pontiff said, "to invite everybody to protect and take care of children so that their smile never fades away, allowing them to live in peace and to look at the future with confidence."
Later, the 84-year-old pope on his first trip to Mexico, said, "You, my little friends, are not alone. You can count on the help of Christ and his Church."