(CN) - Enrique Marquez Jr., the man accused of buying the assault rifles used in the San Bernardino terror attacks last month, pleaded not guilty Wednesday during a brief appearance in the Riverside Federal Court.
A federal grand jury indicted Marquez, a longtime friend of Sayed Rizwan Farook, the male shooter in the San Bernardino terrorist attack, on Dec. 30 on charges of conspiring to provide material support to terrorists.
He was also indicted on two counts of making a false statement in regard to the purchase of two assault rifles that were used in the deadly shooting at the Inland Regional Center, and of marriage fraud and making a false statement on immigration paperwork in relation to an alleged sham marriage with a member of Farook's family.
Marquez told investigators that he and Farook had abandoned plans to mount terrorist attacks on Riverside Community College and on the 91 freeway. Marquez distanced himself from Farook after their plans fell apart, according to his indictment.
Marquez, 24, appeared in the courtroom Wednesday morning wearing a white prison jumpsuit and black glasses, and was chained at the waist. He chatted with his attorney Young Kim prior to the hearing and answered questions from U.S. Magistrate Judge Sheri Pym in a calm, clear and polite tone.
Pym asked for his plea on the terrorism charges.
"Not guilty," Marquez said after informing the judge he was aware of his constitutional rights and had read the indictment.
The case has been referred to U..S. District Judge Jesus Bernal, and Marquez's trial is scheduled to begin on Feb. 23 at 9 a.m. Pym scheduled a status hearing for Feb 8 at 2 p.m.
Marquez is being held without bond in federal custody. If convicted on all counts, Marquez could be sentenced to 50 years in prison.
The hearing a follows a request by the FBI on Tuesday for the public to help them unravel 18 minutes of time, from the attack at the Inland Regional Center to when Farook, a U.S. citizen and Malik, a Pakistani national, were killed in a gun fight.
FBI Assistant Director David Bowdich urged the public to upload any media or cellphone footage that might allow investigators to fill in that unaccounted 18 minutes, between 12:59 p.m. and 1:17p.m.
FBI official Laura Eimiller clarified Tuesday night in an email that authorities believe that at 12:59 p.m. the couple were in an area close to where the 10 freeway intersects with the 215 freeway. By the end of that missing 18 minute gap, the suspects were close to the Waterman exit on the 10 Freeway, investigators believe.
Bowdich clarified the timeline of events after the massacre that covers close to four hours - from the time the couple fled the scene in the black SUV at 11:00 a.m. to the officers-involved gunfight around 3:00 p.m. that ended in their death.
Prior to that time, the black Ford SUV, which had Utah plates and dark tinted windows, had left a residence at 8:37 a.m. and arrived at the Inland Regional Center. Farook had attended the county employee lunch at the social services center before leaving and later returning with his wife to open fire, killing 14 and injuring 22.
Bowdich said it was possible that Malik was waiting in the SUV while Farook was at the party. There is no evidence of a dispute at the party between Farook and his co-workers prior to the shooting, Bowdich said.
Though authorities have uncovered some evidence the couple supported the objectives of Islamic State terrorists, the motives behind the attack remain unclear.
There is no evidence to suggest the couple were directed by Islamic extremists, rather they were "inspired" by terrorists groups, Bowdich said.
Authorities have so far executed 29 search warrants, conducted more than 550 interviews and gathered 500 pieces of evidence.
Bowdich asked the public to call the FBI at 1-800-CALL-FBI (1-800-225-5324) and choose option number 4. From there users can access a special URL to upload video or other media.