The three Secrets of Fatima were written down by one of the children, Lucia Dos Santos - who became a Carmelite nun - and sent to the Vatican in a sealed envelope.
Two of the secrets predicting 20th-century world war, totalitarianism and the eventual reconversion of communist Russia to Christianity were made public.
Pope John Paul II suggested that the third secret predicted the 1981 attempt on his life. But he failed to satisfy conspiracy theorists, with many accusing the Vatican of disclosing only part of the last Fatima secret.
Antonio Socci, a Catholic journalist and author of "The Fourth Secret of Fatima", said he had at first accepted John Paul's explanation. But his researches led him to believe that the late pontiff's revelation had been "partial".
He said the undisclosed portion of the secret predicted a crisis of faith in the West and the collapse of the church hierarchy in the face of a tidal wave of "apostasy and heresy".
But Cardinal Bertone insisted the idea that the secret predicted "catastrophic world events" or the collapse of the Christian church was "pure fantasy".
In his book "The Last Fatima Visionary: My Meetings with Sister Lucia", Cardinal Bertone says that before her death in 2005, at the age of 97, the nun confirmed John Paul's account of the "third secret".
"There is no fourth secret," he declared yesterday. "Everything has been published and correctly interpreted." He hinted that "anti-Christians" were behind the conspiracy theories.
In a preface to Cardinal Bertone's book, Pope Benedict XVI writes that publication of the "third secret" by his predecessor "unveiled the truth amid the confused framework of apocalyptic interpretations and speculation in the church".
Rome denies apocalypse secret (Courier-Mail, 15/5/07)
LINKS (not necessarily endorsed by Church Resources)
Our Lady of Fatima (Wikipedia)
Fatima pilgrims pray for missing girl (CathNews, 14/5/07)
Sister Lucia's remains to be moved to Fatima (CathNews, 17/1/06)
Imminent canonisation of first two Fatima seers (CathNews, 23/2/05)
Last Fatima witness Sister Lucia dead at 97 (CathNews, 15/2/05)
15 May 2007