Superior Court Judge Sim von Kalinowski set Jessica Lynn Lopez's bail at $3 million.
The body of 22-year-old Brittany Killgore was found naked and dumped near Lake Skinner in Riverside County, about 25 miles from her apartment in Fallbrook, on Tuesday. Lopez, 25, was arrested and charged with murder, but prosecutors remain tight-lipped about a possible motive.
"This case has shaken many in San Diego County and many in the military community at Camp Pendleton," said Bonnie Dumanis, San Diego County District Attorney. "I will not respond to rumors or speculation regarding this case."
Investigators say a suicide note written by Lopez told them where to find Killgore's body.
Lopez faces 25 years to life in prison if convicted. She is due back in court May 2 for a hearing to determine if there is enough evidence for her to stand trial.
Another Camp Pendleton Marine, 45-year-old Louis Ray Perez, is considered a person of interest in the case. Police believe he was the last person seen with Killgore. He has been arrested on an unrelated weapons charge.
Authorities aren't saying how Perez or Lopez are connected to Killgore.
Brittany Killgore disappeared four days after she filed for divorce from her husband, Lance Cpl. Cory Killgore, who has been serving a tour of duty in Afghanistan. He is returning to Southern California on emergency leave due to the investigation. Authorities say he is not a suspect.
Brittany Killgore's family says they are devastated.
"Brittany was a victim. She did nothing wrong. There have been stories and comments from people who do not know my daughter," said father Darryl Wrest.
City News Service contributed to this report.