John Mark Karr, who was briefly a suspect in the JonBenet Ramsey slaying, is expected to be arraigned on child pornography charges Wednesday in a Sonoma County courtroom.

Karr, 41, arrived at Oakland International Airport late Tuesday with considerably less fanfare than when he was greeted by a crowd of reporters in Los Angeles last month after he flew from Thailand, where he was arrested.

"I was heading back to the bathroom and as I walked back I saw him," said one passenger on the flight. "He was with two federal marshals."

Witnesses said Karr quickly exited a commercial flight, walked down the tarmac and left the airport in a vehicle with tinted windows. He is being held without bail at the Sonoma County jail in Santa Rosa and is scheduled for arraignment on five misdemeanor counts of possessing child pornography at 8:30 a.m. Wednesday.

"He was in 34A right by the bathroom in the back. It was creepy. Just scum, you know. These guys put in jail once should stay there," said passenger Sharon Nichols.

Karr, who had been held in Colorado for several weeks, was released by Boulder County authorities earlier Tuesday.

Sonoma County deputies initially went to pick up Karr on Sept. 7 but abandoned the effort "due to an evolving prospect of federal authorities adopting our 2001 misdemeanor charges for federal prosecution," sheriff's Lt. Dave Edmonds said in a written statement. "At this point, we have excluded this option."

Karr, a schoolteacher, was arrested Aug. 16 after he made phone calls and wrote e-mails in which he claimed to have killed the 6-year-old beauty queen in her Boulder home in December 1996.

But DNA tests failed to connect Karr to the crime, and investigators had no evidence he was even in Boulder at the time of the slaying.

Colorado prosecutors later said it was difficult to separate fact from fantasy in Karr's confessions.

Five misdemeanor counts of child pornography possession have been pending against Karr in Sonoma since April 2001, when authorities arrested him and seized his computer, alleging that the hard drive contained five sexually oriented images of children.

Karr pleaded not guilty to all counts and was jailed for six months, but he left the country before he could be tried. Prosecutors decided to pursue the charges after Karr surfaced last month as a suspect in the JonBenet killing.

During preliminary hearings in 2001, Karr's public defenders waived his right to a speedy trial as they tried to get a judge to invalidate the search warrant that allowed Sonoma sheriff's deputies to enter Karr's home and seize his computer.

If convicted of the Sonoma child pornography charges, Karr could get a year in prison on each count. Authorities have also said they want to re-examine Karr's computer for more illicit images.