Enrique Marquez Jr., the man who purchased two weapons used to kill 14 people inside a San Bernardino social services center earlier this month, was indicted Wednesday on additional charges related to the deadliest terrorist attack on U.S. soil since Sept. 11, 2001.

Prosecutors unveiled a superseding indictment that brings the total number of charges against Marquez to five. If convicted on all charges, he faces up to 50 years in federal prison.

Marquez, 24, emerged as a central figure in the investigation after federal agents began to probe his ties to gunman Syed Rizwan Farook. The two onetime neighbors became close friends and began attending a mosque together in 2010. Even as Marquez told friends he hoped to enlist in the U.S. Navy, prosecutors say, he and Farook were secretly amassing weapons, discussing radical Islam and plotting terrorist attacks in California.

Farook and his wife, Tashfeen Malik, were killed in a firefight with police hours after the Dec. 2 attack.


Marquez had already been charged with supplying the weapons that Farook and Malik used to attack the Inland Regional Center, and with providing the smokeless powder contained in an explosive device found at the scene of the attack. Marquez admitted that he purchased the powder in 2011 while plotting other attacks with Farook, according to an affidavit filed in the case.

According to court records, the two had plotted to launch attacks on the 91 Freeway in Corona and at Riverside City College in 2011 and 2012, but both plots were aborted, records show.

On Wednesday, prosecutors modified the charges against Marquez, claiming he made false statements when obtaining each of the semiautomatic rifles used in the attack, which were purchased in 2011 and 2012. Farook had Marquez acquire the weapons because he feared he would not pass a background check, investigators have said.

Prosecutors also accused Marquez of marriage fraud.


In 2014, Marquez married Mariya Chernykh, a Russian national whose sister is married to Farook’s older brother. But the circumstances of the marriage have come under federal suspicion in recent weeks. Marquez said in immigration papers that the two lived together, but records show Chernykh lived in Ontario while he lived in Corona. He also told authorities he was paid to marry Chernykh.

Marquez remains in federal custody without bond and is scheduled to appear in a U.S. District Court in Riverside on Wednesday.

“Mr. Marquez is charged for his role in a conspiracy several years ago to target innocent civilians in our own backyard with cold-blooded terror attacks, and with providing weapons to an individual whose endgame was murder,” David Bowdich, assistant director in charge of the FBI’s Los Angeles field office, said in a statement.

“The covert nature of the defendant’s alleged actions is a stark reminder of the challenges we face in preventing attacks planned in the name of violent jihad, and underscores the critical need for those with knowledge about terror plots to come forward,” Bowdich said.


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Prosecutors have not accused Marquez of taking an active role in the Dec. 2 shootings, and it remains unclear whether he had prior knowledge of Farook and Malik’s plans. Hours after the shooting, Marquez called 911 to say that Farook had used his gun in the attacks. He also posted a cryptic apology on his personal Facebook page on the day of the attack, before going to an emergency room and then being sent to a mental health institution.

Marquez repeatedly waived his right to an attorney and voluntarily spoke with federal agents, who are trying to determine the shooters’ connections to larger terror networks. Malik pledged allegiance to Islamic State in a Facebook post published a short time before the shootings, but investigators do not believe the husband and wife were directed to carry out the attacks by a foreign terrorist cell.

In the previous complaint, prosecutors detailed how Marquez and Farook planned to hurl pipe bombs at cars on a section of the 91 Freeway that lacked nearby exits. After creating a traffic jam, Farook planned to stalk between vehicles, shooting motorists, while Marquez opened fire on first responders from a different vantage point.


The two had also plotted to conduct a similar attack at Riverside City College, where Marquez had attended classes.

richard.winton@latimes.com

james.queally@latimes.com

Follow @lacrimes and @JamesQueallyLAT for breaking news.


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