Jared Lee Loughner, the man accused of shooting Arizona Rep. Gabrielle Giffords (D), was orderd to be held without bail by a federal judge on Monday.

Judge Lawrence Anderson also set Loughner's preliminary hearing for Jan. 24 at 1:30 p.m. Mountain time.

According to The Associated Press, Loughner appeared in a federal courtroom in Phoenix donning a tan inmate jumpsuit and a shaved head.

Loughner, 22, is accused of killing six and wounding 14 in a shooting spree at a meet-and-greet for Giffords's constituents in Tucson, Ariz., on Saturday. Among those killed were federal district Judge John Roll and Giffords aide Gabriel Zimmerman. Giffords suffered a gunshot wound to the head. 

Loughner faces five federal charges: the attempted assassination of Giffords, the killing of Roll and Zimmerman, and the attempted killing of staffers Pamela Simon and Ron Barber, who were carrying out their duties as federal officials.

Due to the high-profile nature of the case, state and federal law enforcement agents surrounded the courthouse and about a dozen U.S. Marshals guarded the courtroom.

Representing Loughner during the hearing was well-known defense attorney Judy Clarke, who represented the "Unabomber" Ted Kaczynski and Oklahoma City bomber Timothy McVeigh. Clarke also assisted in the case of convicted al Qaeda member Zacarias Moussaoui, who helped the plot to take down the World Trade Center in  New York on Sept. 11, 2001.