BOULDER, Colo. -- If the stunning confession in JonBenet Ramsey's slaying has made the decade-old case any easier to solve, prosecutors aren't saying. And it may have made it more puzzling.

Hours after John Mark Karr told reporters in Thailand he was with JonBenet when she died, questions arose about his claims -- including whether he sexually assaulted the 6-year-old beauty queen or was even in Colorado at the time of the slaying.

"It's clear to me that he's somewhat interested or maybe even obsessed by the case and the real question is whether he's inserting himself into it for some obscure psychological reason," said author Carlton Smith, who wrote 1997's "Death of a Little Princess: The Tragic Story of the Murder of JonBenet Ramsey."

Newspaper Publishes E-Mails

On Friday, the Rocky Mountain News published what it said were e-mails from Karr about the Ramsey case. The newspaper said the emails came from a source close to the investigation.

One e-mail said in part, "JonBenet, my love, my life. I love you and shall forever love you. I pray that you can hear my voice calling out to you from my darkness -- this darkness that now separates us," the News reported.

The newspaper said the message was part of a small sample of correspondence between Karr and Tracey. In other e-mails, Karr said he was under federal investigation for "child murder and child molestation" in four states.

In Washington, federal law enforcement officials said Karr's comments since his arrest have piqued their interest and they want to question him. Regarding Kerr's purported claims in emails that he was under federal investigation for child murder and molestation, one law enforcement official said "there is no four-state federal case" in which Karr is wanted or even suspected. The official spoke on condition of anonymity because the case is being handled by local prosecutors in Colorado.

In another e-mail, the Rocky Mountain News reported, Karr said he sympathized with Michael Jackson, who has been accused of molesting young boys.

"I will tell you that I can understand people like Michael Jackson and feel sympathy when he suffers as he has," Karr wrote.

"I can relate very well to children and the way they think and feel," one Karr e-mail said. "I think you are asking if I am much a 'Peter Pan.' In many ways, the answer is yes. In other ways, I suppose it is no because I am trapped in a world that does not understand."

In one correspondence, Tracey asked whether Karr's "fascination with little girls -- which clearly has a strong erotic component -- is a way of going back."

"Maybe I am not going back but have simply stayed consistent," Karr responded. "My peer group has not changed since I was a little boy, and girls were the people I was with always. Referring to them as a peer group is somewhat incorrect, but might also be the very definition of what they continue to be in my life."

Tracey refused to discuss the e-mails with reporters on Thursday and declined comment for the newspaper story.

Report: Karr Gave Unpublished Info About Body

A U.S. law enforcement source told CNN on Friday that Karr gave authorities graphic details about the condition of JonBenet Ramsey's body that have been kept secret for nearly a decade.

The details, the law enforcement official said, were known only to the medical examiner and the investigators probing the her slaying,

Earlier, District Attorney Mary Lacy refused to say whether authorities have evidence linking Karr to JonBenet's death at her Boulder home on Dec. 26, 1996.

"We should all heed the poignant advice of John Ramsey," said Lacy, quoting the girl's father. "Do not jump to conclusions, do not rush to judgment, do not speculate. Let the justice system take its course."

Sources told 7News that Karr was expected to arrive sometime this weekend.

Police Official Changes Account

Lt. Gen. Suwat Tumrongsiskul of the Thai immigration police changed some details Friday of the account he had given of what Karr told investigators. In a telephone interview Thursday with The Associated Press, Suwat quoted Karr as saying he had sexually assaulted the girl and given her drugs. He also told reporters before a news conference Thursday that Karr had claimed to have picked up JonBenet at her school.

On Friday, Suwat confirmed to the AP his account of the sexual assault. But asked Friday if Karr gave the girl drugs, Suwat said the suspect described the encounter with JonBenet Ramsey as "a blur."

"It may have been drugs, or it may have been something else because (Karr said) it was a blur, blur," Suwat said.

Suwat also said Friday that his statement about the girl being picked from school was based on a documentary he had seen and not the interrogation.

JonBenet's autopsy report found no evidence of drugs, saying her death was caused by strangulation after a beating that included a fractured skull. While it describes vaginal injuries, it makes no conclusions about whether she was raped. Investigators later concluded there was no semen on JonBenet's body.

Ex-Wife Gives Karr Alibi

Karr's ex-wife, Lara Knutson, told reporters she cannot defend him, then insisted he was with her in Alabama that Christmas.

"She cannot think of a Christmas while they were together when he was away from the family on Christmas day or immediately thereafter," said her attorney, Michael Rains, though he added she could not specifically recall Christmas 1996.

Authorities have not said whether Karr could have written the ransom note demanding $118,000 found in the Ramsey home. And the professor who swapped four years' worth of e-mails with Karr and brought him to the attention of prosecutors in May refused to characterize the suspect either as killer or kook.

"I don't know that he's guilty," said Michael Tracey, who teaches journalism at the University of Colorado. "Obviously, I went to the district attorney for a reason, but let him have his day in court and let JonBenet have her day in court and let's see how it plays out."

Any previous relationship between Karr and the Ramseys remained a mystery, though both have ties to suburban Atlanta.

Karr's Background

Karr's background includes an arrest in Petaluma, Calif., in 2001 on five misdemeanor counts of possession of child pornography, to which he pleaded not guilty.

He began teaching at Bangkok Christian College, an elite private school with about 5,500 male students in 12 grades, in early June, school officials said. He worked there for about two weeks before being dismissed.

"He was qualified to be a teacher. He had a diploma and has experience in teaching in Bangkok for some time," said Banchong Chompowong, assistant director of the English immersion program at Bangkok Christian. "John Karr came to us with a good resume and with credentials, but then we allowed him a trial (period) with students, we found he was too strict."

Banchong said Karr gave the students "time outs" and another teacher said he had a reputation for yelling at students.

Karr was arrested at a Bangkok apartment Wednesday. Hours later, Thai authorities sat him before a room of journalists, where he admitted: "I was with JonBenet when she died. Her death was an accident."

"I am so very sorry for what happened to JonBenet," Karr told the AP.

Suwat said Karr wants to return to the United States to fight the case. He said U.S. authorities were preparing documents and plane tickets for the return journey. The departure could take place at any time, he said.

Thai police said Karr told them the slaying was second-degree murder. One expert suggested his confession was geared to spare him a first-degree murder charge.

"He seemed convinced that what he said would make him guilty of a lesser crime," said Sharon Davies, a former prosecutor at the Ohio State University law school.

DNA Key To Case

Legal experts said DNA evidence will likely be key: DNA was found beneath JonBenet's fingernails and inside her underwear, and authorities have never said whether it matches anyone in an FBI database.

Karr was given a mouth-swab DNA test in Bangkok, according to a law enforcement official who spoke on condition of anonymity because of the ongoing investigation. The results of that test were not known. Karr will be given another DNA test when he returns to the United States in the next several days, the official said.

It is known that DNA evidence was collected at the Ramsey crime scene and that it did not match anyone in the Ramsey family.

Attorney: Karr Had Info Not Previously Disclosed

Asked if authorities could tell whether Karr had firsthand knowledge of the murder or had just picked up information from news accounts, Lin Wood, the Ramseys' longtime attorney, said: "There is information about the murder that has never been publicly disclosed." He did not elaborate.

Wood said he believes there is more to the case than correspondence.

"I feel like there must be something more here than some e-mail confession," the attorney said, although he said there have been similar confessions in the past.

"There have been e-mail confessions in the case before," Wood said Friday. "John Ramsey has received e-mail confessions in the past and nobody was arrested."

Karr's description of the case as an accident also rang false to experts.

"It's hard to imagine a more intentional, deliberate murder," said Craig Silverman, a former Denver prosecutor, referring to JonBenet's skull fracture and strangulation. "This has always been a case of deliberate murder."

"You don't have a smoking gun at this point, what you have is a smoking mouth," said one legal expert, talking to ABC News.