BOULDER, Colo. -- In a stunning twist to what was already a bizarre story, the district attorney on Monday abruptly dropped the case against John Mark Karr because DNA failed to put him at the crime scene where JonBenet Ramsey was killed.

"The warrant has been dropped by the district attorney. They are not proceeding on this case," said Seth Temin, Karr's public defender. He spoke at an impromptu news conference outside the Boulder County Jail.

Karr, a 41-year-old schoolteacher, was returned to the United States a week ago from Thailand, where he told reporters that he had been with JonBenet when she died, but that her death was an accident.

"We're deeply distressed by the fact that they took this man and dragged him here from Bangkok, Thailand, with no forensic evidence confirming the allegations against him and no independent factors leading to a presumption that he did anything wrong," said Temin.

Temin didn't refer specifically to the DNA evidence but according to a court motion filed on Monday, DNA testing failed to make a match between Karr and the DNA found in the Ramsey home.

In the motion to quash the arrest warrant, District Attorney Mary Lacy said that as soon as Karr arrived in Boulder County last Thursday, a cheek swab was taken from him and sent to a Denver crime lab for testing to compare his DNA profile with the DNA from the scene of the crime.

The DNA test, completed on Saturday, concluded that "Mr. Karr was not the source of the DNA found in the underwear of JonBenet Ramsey. This information is critical because, as mentioned above, if Mr. Karr's account of his sexual involvement with the victim were accurate, it would have been highly likely that his saliva would have been mixed with the blood in the underwear," according to the affidavit.

According to court papers, Karr told the journalism professor whom he was corresponding with that he accidentally killed JonBenet during sex and that he tasted her blood after he injured her vaginally.

"Wherefore, because no evidence has developed, other than his own repeated admissions, to place Mr. Karr at the scene of the crime and, in particular, because his DNA does not match that found in the victim's blood in her underwear, the People would not be able to establish that Mr. Karr committed this crime despite his repeated insistence that he did," the affidavit said.

According to the affidavit to dismiss the case, Karr's family also provided strong circumstantial support that Karr was with them in Atlanta, Ga., at the time of the murder.

"We knew it all along. We never had a doubt," said John Karr's brother, Nate, after the district attorney's stunning announcement.

Authorities also found no evidence Karr was in Boulder at the time of the slaying, 7NEWS reported. There were no credit card receipts, no phone records, no motel records -- nothing that connected Karr to Boulder during Christmas, 1996.

Karr To Be Extradited To California

What was to be Karr's advisement hearing, scheduled for Monday afternoon, was canceled.

Karr is no longer being held for any Colorado charges but will remain in jail to await extradition to California, said Boulder County sheriff Joe Pelle.

Pelle said Karr will be held in the same jail cell where he's been since last week. He described Karr as "polite and cooperative." Karr has a 4 p.m. extradition hearing at the Boulder County Justice Center on Tuesday.

He faces child pornography and failure-to-appear charges in Sonoma County, Calif. Karr was arrested in Petaluma, Calif., in 2001 and pleaded not guilty to five misdemeanor counts of possession of child pornography. He fled before he could be tried and still faces an outstanding warrant there.

Authorities there had said he made "uncertain allusions to placing himself in the killer's role" in talking about JonBenet and 12-year-old Polly Klaas, who was slain in 1993 in Petaluma, Calif.

Did District Attorney Move Too Fast?

After Karr was detained in Bangkok a week and a half ago, Lacy told a news conference that sometimes it becomes necessary to make an arrest before an investigation is complete and that much work remained in the Karr investigation. Prosecutors had always said that the case is still in its "very early stages" but never revealed exactly what evidence they had against Karr.

Apparently, all they had were bizarre e-mails and correspondence where Karr claimed intimate knowledge about the killing -- but that is not enough to convict, 7NEWS reported. The e-mails, although disturbing and specific, could have been concocted by anyone obsessed with the 10-year-old case since most of the details about the girl's death had been on the Internet for years, including the theory that a flashlight was used to strike the fatal blow.

Boulder investigators said they got DNA samples from Karr in Thailand but not enough to conclusively link him to the case or rule him out. And when they initially tried to get a DNA swab in Thailand, Karr refused.

Lacy claimed in a motion to kill the case that until Karr was identified, "there was no way to try to confirm or disprove his admissions related to causing the death of JonBenet Ramsey until he was detained."

Still, many are now left wondering why investigators went halfway around the world to arrest him.

One person who appears to be upset by the district attorney's debacle is Colorado's governor.

"Unfortunately, the hysterics surrounding John Mark Karr served only to distract Boulder officials from doing their job, which should be solving the murder of JonBenet Ramsey. I find it incredible that Boulder authorities wasted thousands of taxpayer dollars to bring Karr to Colorado given such a lack of evidence. Mary Lacy should be held accountable for the most extravagant and expensive DNA test in Colorado history," Owens said Monday.

One reason why investigators may have acted quickly was because Karr began to describe an interest in several girls in Thailand "in much the same terms that he had described his interest in JonBenet," Lacy wrote in an affidavit.

Authorities were able to confirm that he "was having personal involvement with at least one of the girls," Lacy said. He was arrested a short time later.

Inconsistencies in Karr's account immediately raised suspicions that he might be an obsessed follower of the case who confessed to a crime he didn't commit.

Scott Robinson, a Denver attorney who has followed the case from the beginning, said Lacy had no choice but to pursue the lead. He said Karr may be charged with lying about his role in the case.

"Seems to me there should be some criminal consequences," he said. "He has cost the taxpayers an enormous amount of money."

Back To Square One

Lacy vowed to keep pursuing leads in JonBenet's death.

"As I said last week, our role in the investigation of JonBenet Ramsey's murder has been to follow up on all legitimate leads that we have received from law enforcement and concerned citizens. This case is not closed, and we will continue to investigate leads and pursue justice," Lacy said.

Lacy plans to discuss the case and the process and procedures regarding Karr's arrest at a media briefing on Tuesday at 10 a.m.

Karr's arrest in Thailand was regarded as a remarkable break in the decade-old murder mystery that had cast suspicion on JonBenet's parents and led to myriad theories about the killer.

JonBenet's parents, John and Patsy Ramsey, were initial targets of a grand jury investigation that ended with no indictments. Patsy Ramsey died in June after learning authorities had turned their attention to Karr.

Karr emerged as a suspect in April after he spent several years exchanging e-mails with University Colorado professor Michael Tracey in which Karr admitted responsibility for the slaying and provided grisly details, Lacy said.

"By becoming so sexually involved that he lost track of time so that the asphyxiation lasted longer than he intended, causing her severe injury, leading him to inflict a severe blow to her head," Lacy had written in the arrest warrant.

But in the hundreds of e-mails and hours of phone calls with Tracey, which were all released Monday evening by the district attorney's office, it is clear that Karr was using Tracey to live out his fantasies about JonBenet. He even made it clear he wanted to be part of Tracey's proposed book on the murder.

JonBenet Ramsey's aunt, Pamela Paugh, said she was disappointed there won't be a prosecution of someone in the case, but she is glad that justice has been done.

"I think our justice system worked as it was supposed to," said Paugh, who is Patsy Ramsey's sister. "We asked the DA to do her thing. She did it."

Paugh added: "My disappointment came about the end of December 1996 when we didn't have the killer then. We've had 9 1/2 years of disappointment and waiting."

Gary Harris, who had been spokesman for the Karr's brother and father, said he knew the DNA wouldn't match.

Karr has been "obsessed with this case for a long time. He may have some personality problems, but he's not a killer," Harris said. "He obsesses. He wanted to be a rock star one time. ... He's a dreamer. He's the kind of guy who wants to be famous."

More: Special Ramsey Case Section