Enrique Marquez, a friend and former neighbor of San Bernardino shooter Syed Rizwan Farook, has been indicted by a federal grand jury, the U.S. Department of Justice announced Wednesday.

Marquez, 24, who was arrested two weeks ago, is charged with conspiring to provide material support to terrorists, as well as two counts of making a false statement regarding the purchase of assault rifles, one count of marriage fraud and one count of making a false statement on immigration paperwork, according to the Associated Press.

"This indictment demonstrates that we will hold accountable all individuals who collaborate with terrorists in executing their plans," U.S. Attorney Eileen M. Decker said in a statement.

"Defendant Marquez's extensive plotting with Syed Rizwan Farook in 2011 and 2012, and his purchase of explosive powder and two firearms provided the foundation for the murders that occurred this month," she added, according to NBC News.

A federal complaint accompanying the charges reveals that Marquez and Farook planned in 2011 to carry out a pipe bomb attack at Riverside College and on a section of the 91 Freeway. Details about the attack on Riverside College, where they were both students at the time, weren't released, but there is much more information about the freeway attacks. Their alleged plan was to throw the bombs onto the freeway after creating a traffic jam, and while Farook would shoot those trapped in their cars, Marquez would fire at first responders from a vantage point.

The attack was never carried out, but the complaint revealed that the both the guns, which Marquez admitted to buying so Farook wouldn't have to face a background check, and the contents of the pipe bomb, which Marquez is also believed to have brought, were found at the scene of the San Bernardino attack.

Marquez is being held without bail following a Dec. 21 hearing where a judge determined he was a flight risk and ordered that he must remain within police custody. 

He has not entered a plea and will be arraigned Jan. 6.