An American man was arrested in Bangkok as a suspect in the 1996 death of JonBenet Ramsey, the 6-year-old girl from Boulder, Colorado, whose unsolved killing became a media obsession, prosecutors said Wednesday. Local officials would not name the suspect, but two sources familiar with the arrest, including the lawyer for the Ramsey family, identified him as John Mark Karr, 41, a former schoolteacher who once lived in Conyers, Georgia. Karr was arrested on sex charges unrelated to JonBenet's slaying after several months of investigation, said officials. Boulder County District Attorney Mary Lacy said investigators from her office were heading to Thailand to question the suspect and bring him to Colorado. Lawyers said this could take days or weeks, depending on whether Karr contests his extradition and whether Thailand decides to expel him.