The suspect in the January shooting rampage in Tucson has been transferred to a specialized facility in Missouri to undergo a court-ordered mental evaluation.

Lawyers for 22-year-old Jared Lee Loughner say in a court filing that he was taken from Tucson to a federal Bureau of Prisons medical facility in Springfield, Mo., on Wednesday.

The lawyers want an appeals court to order him returned.

Loughner will be given tests to determine if he understands the nature and consequences of the charges he faces and can assist in his defense.

Loughner has pleaded not guilty to charges stemming from the Jan. 8 attack that killed six and wounded 13, including Rep. Gabrielle Giffords. She remains at a rehabilitation center in Houston as she recovers from a bullet wound to the brain.