The mystery surrounding the assassination of President John F. Kennedy has taken a dramatic new twist following the discovery of new documents in an old safe at the Dallas County district attorney's office.

Most intriguing among the new material is a transcript perportedly recording a conversation between assassin Lee Harvey Oswald and his own killer Jack Ruby, in which the two discuss how to eliminate the president.

While the district attorney's office dismissed the document as a fictional account intended for use in the making of a movie, conspiracy theorists will leap on the new material.

Much of the attention is bound to focus on the transcript purporting that Ruby and Oswald met at Ruby's nightclub on Oct. 4, 1963, less than two months before the Nov 22 assassination.

In it, they talked of killing the president because the Mafia wanted to "get rid of" his brother, Attorney General Robert Kennedy.