ALEXANDRIA, La. — Thomas Steven Sanders pleaded not guilty Friday morning to kidnapping 12-year-old Lexis Kaye Roberts, whose remains were found in October in the woods outside of Harrisonburg.

Sanders faced Magistrate Judge James D. Kirk at the U.S. District Court in Alexandria, a court spokesperson confirmed.

Sanders was arraigned Friday morning after being indicted by a federal grand jury on Thursday.

Sanders will face first-degree murder charges from the Catahoula Parish Sheriff’s Office after the federal government finishes processing him.

Sanders is also a suspect in the disappearance of Lexis’ mother, 31-year-old Suellen Roberts.

Investigators are working to determine if a body found Monday morning in Arizona belongs to Suellen.

If the body is that of Suellen, Sanders could also face charges in an Arizona state court.

A hunter found the body of Lexis Roberts on Oct. 8.

Investigators believed her body was in that location for approximately a month before she was found.

Lexis and Suellen were both last seen traveling with Sanders.

A security video from a Las Vegas Walmart shows Sanders purchasing ammunition on Sept. 3.

The caliber of the bullets purchased matched the caliber of those with which Lexis was killed.

Sanders, who was legally pronounced dead in 1994 by family members, was arrested at a Gulfport truck stop at approximately 7 a.m. on Sunday.

Authorities had been searching for Sanders since Oct. 27.

According to a statement from the U.S. Attorney’s Office, a conviction of kidnapping resulting in the death of the victim can result in either a life sentence or death.

The federal death penalty statute requires the government to file additional pleadings if the decision is made to seek the death penalty.

The government made no such pleadings in the case, and Sanders maximum penalty if convicted is life in prison.