Jared Loughner, the suspect in Saturday's rampage shooting in Tucson, the U.S. state of Arizona, appeared in court on Monday afternoon to face felony charges.

Jared Loughner, the suspect in rampage shooting in Tucson, the U.S. state of Arizona, appeared in court on January 10, 2011, to face felony charges. [China.org.cn]

The Sandra Day O'Connor Federal Courthouse in Phoenix was heavily guarded by police officers and Department of Homeland Security agents as the brief hearing was going on.

The appearing was presided over by U.S. Magistrate Lawrence Anderson who informed Loughner of the penalties he could face if he is found guilty of the crimes.

Wearing a tan detention uniform with his head shaven, Loughner answered questions in a deep, resonant voice. But most of the time he remained silent.

Loughner, 22, was accused of killing six people and wounding 14 others, including U.S. Congresswoman Gabrielle Giffords of Arizona, at a gathering outside a grocery store in Tucson on Saturday.

U.S. District Judge John Roll and Gabe Zimmerman, a Giffords aide, were among the victims killed in the shooting, which presumably targeted Giffords.

Giffords, 40, was shot in the head and underwent surgery. She remains in critical condition and it was unknown whether she will be able to return to Congress.

Loughner could receive up to life in prison if convicted of shooting Giffords, and up to 20 years if convicted in the shootings of two other congressional aides.

Loughner also is expected to face a series of charges in state courts.

As expected, Anderson appointed noted defense attorney Judy Clarke of San Diego as Loughner's attorney.

Clarke waived a detention hearing and Anderson, on the recommendation of Assistant U.S. Attorney Wallace Kleindienst, remanded Loughner to detention pending a Jan. 24 hearing.

Clarke also demanded that the U.S. Attorney's Office in Phoenix be conflicted out of the case.

"There is great concern with proceeding any further than today with Arizona judges," Clarke said.

As the hearing ended, Anderson turned to the defendant and said: "Good luck to you, Mr. Loughner. We are adjourned."

The motive for the killing remains unknown. Loughner has not been cooperating with investigators, authorities said.

Official sources familiar with the investigation said local authorities are looking at a possible connection between Loughner and the American Renaissance, an online group known for its anti- government rhetoric.

The group is reportedly connected to the white supremacist New Century Foundation.