Prosecutors say the centerpiece of their sex-abuse case against Michael Jackson will be a dozen or more explicit letters and poems believed written by the pop music superstar, which police seized during raids on Jackson’s Neverland ranch last week.

Yesterday, a source close to the investigation said, “The district attorney is convinced these letters will be crucial to the case against Jackson,” according to a report in the Sydney Daily Telegraph. “The boy told investigators about letters and poems and their precise location inside Michael’s home. These letters were among the evidence seized, along with videotapes. They are very explicit and intimate and show a degree of familiarity. Basically, they appear to be love letters from Michael to the boy.”

Thirteen-year-old cancer victim Gavin Arvizo, who Jackson stands accused of sexually molesting, told law enforcement authorities the pop star’s pet name for him was “Rubba.”

According to the Telegraph’s source, “The boy first told this to his therapist, then repeated it to police. He said Jackson called him Rubba because one of the games they used to play was called rubba rubba. The boy said, ‘Michael told me he was my rubba rubba friend.”‘

Gavin’s mother, Janet Ventura, says Jackson encouraged the boy to call him “Daddy.”

For their part, Jackson’s defense attorneys plan to vigorously attack Ventura’s credibility, according to a Fox News report, which says the defense team already has videos in which both mother and boy say they love Jackson and have never seen inappropriate behavior, as well as written statements saying the same thing.

The documents, says the report, were signed late February by the boy and his mother in the presence of Jackson attorney Mark Geragos. In addition, Fox reports the Jackson team has received many calls from witnesses who were present at Jackson’s Neverland Ranch when the boy was there, who corroborate the story that the boy was happy and all was well.

Other witnesses in the wings, says the Fox report, including employees of Jackson, will testify that they saw Gavin’s mother, high on crack, arguing with him and making demands. Sources close to Jackson also told Fox they believe the sexual-molestation case is really just about the mother’s greed – adding that for almost a year she has made verbal threats saying, “she could go to the tabloids and tell some stories if they didn’t take care of her.”

Thursday, a handcuffed Michael Jackson walked into a Santa Barbara sheriff’s station to be booked on multiple counts of child molestation. The arrest warrant was issued by Santa Barbara County law-enforcement authorities following an extensive police search of Jackson’s Neverland ranch last Tuesday. The warrant, based on allegations brought by the 13-year-old Arvizo, details a violation of Section 288(a) of the California Penal Code – which prohibits lewd or lascivious acts with a child under age 14.

Michael Jackson’s mug shot

After posting $3 million bond and surrendering his passport, Jackson was released. His attorney, Mark Geragos, said the pop star is ”outraged” by the charges and considers the accusations ”a big lie,” adding that Jackson looks forward to getting into a courtroom to ”confront the charges head on.”

Michael Jackson led into booking in handcuffs.

In a statement, Jackson spokesperson Stuart Backerman said: “The outrageous allegations against Michael Jackson are false. Michael would never harm a child in any way. These scurrilous and totally unfounded allegations will be proven false in a courtroom.”

Jackson’s career began to nosedive after the 1993 child-molestation allegations surfaced.

Earlier this year, WorldNetDaily reported the graphic details of the sexual relationship the boy says he and Jackson shared.

As WorldNetDaily reported, Jackson admitted in a February television documentary that he loves to have young boys sleep in his bed.

Although he claimed only “very few” boys had actually stayed in his bed, Jackson strongly defended the practice, saying: “Why can’t you share your bed? The most loving thing to do, is to share your bed with someone.”

According to the Telegraph, a source close to the case’s prosecutor, District Attorney Tom Sneddon, said: “The DA is very confident with the evidence he has. This includes letters, videos and computer files. They believe they have enough to nail Jackson.”

Jackson’s arraignment is scheduled for Jan. 9 in Santa Barbara Superior Court.

Related stories:

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Arrest warrant issued for Jackson

Cops search Michael Jackson’s ranch

Boy’s bombshell: Michael Jackson had sex with me

Michael Jackson confesses: I sleep with boys

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