RIVERSIDE, Calif. (KABC) --Enrique Marquez, the man accused of buying the rifles used in the San Bernardino attack, pleaded not guilty on Wednesday to multiple charges in a federal indictment accusing him of conspiring with one of the shooters and to provide material support to terrorists.
Marquez appeared in federal court in Riverside wearing an all-white prison jumpsuit with his feet shackled and his hands cuffed. He answered several questions from the judge with "yes your honor" and answered "not guilty" when asked to enter his plea to the indictment.
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The 24-year-old faces five charges, including conspiracy to support terrorism.
Prosecutors said there's no evidence at this point that he knew about Syed Farook and his wife Tashfeen Malik's plans to open fire at the Inland Regional Center in December.
However, they did say Marquez provided them with their assault rifles and that his failure to warn authorities about his purchase of the guns had deadly consequences.
Marquez was a former neighbor and friend of Farook. The two grew up next door to each other in Riverside. Farook introduced Marquez to Islam as a teenager a decade ago and indoctrinated him in violent extremism, according to the FBI.
The attack in San Bernardino killed 14 people and wounded 22 others. Farook and Malik opened fire at a building where Farook's colleagues from the San Bernardino county health department were meeting.
According to prosecutors, Marquez bought two rifles for Farook in 2011 and 2012 and the two planned to launch bomb and shooting attacks at Riverside City College, where they attended classes, and a notoriously gridlocked section of highway without exits.
The two never carried out those plans.
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Marquez faces two counts of firearms violations for being the so-called straw buyer who purchased the guns in his name because Farook, who was born in the U.S. to Pakistani immigrants, "looked Middle Eastern," authorities said.
He also faces one count of marriage fraud and one count of making a false statement on immigration paperwork for his marriage to a Russian woman whose sister is married to Farook's brother.
The FBI said Marquez admitted he was paid $200 to marry the woman and he lied on immigration papers that he lived with her so she could stay in the U.S.
If convicted on all charges, Marquez faces up to 50 years in prison. A jury trial was scheduled for Feb. 23. The prosecutor estimates the trial could last about two weeks.
The Associated Press contributed to this report.