WASHINGTON (CBSDC/AP) — A man accused of shooting a security guard at the Washington headquarters of a conservative lobbying group has pleaded not guilty to assault and handgun charges.

Floyd Lee Corkins, of Herndon, Va., faces the possibility of decades in prison if convicted in the attack on Leo Johnson inside the lobby of the Family Research Council. Authorities say Corkins told the guard he didn’t like the group’s politics before opening fire and that he was carrying 15 Chick-fil-A sandwiches.

Corkins pleaded not guilty at an arraignment Friday afternoon. A judge also ruled during the hearing that Corkins was competent to understand the court proceedings and assist in his defense. Corkins waived the right to a detention hearing and will be held without bond until his next court appearance, which has not been scheduled.

(TM and Copyright 2012 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2012 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)