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Story highlights

Enrique Marquez faces federal charges in connection with the San Bernardino terrorist attack that killed 14 people

Those who remember him say he was mild-mannered, but none says Marquez was a particularly close friend

"He would be the last person on earth I would suspect," says the man who hired him to check IDs at his bar

Riverside, California CNN —  

“No one really knows me,” the Facebook posting read. “I lead multiple lives and I’m wondering when it’s all going to collapse on me.”

Enrique Marquez, then an innocuous Walmart employee and part-time security guard at a bar, made this foreboding post on November 5.

The answer to Marquez’s online musings came Thursday, when federal prosecutors charged him in connection with the December 2 terrorist attack in San Bernardino that claimed the lives of 14 people.

Marquez, 24, a childhood friend and neighbor of killer Syed Rizwan Farook, is accused of illegally purchasing a pair of rifles that were used in the attack by Farook and his wife, Tashfeen Malik. He also is accused of the more serious offense of conspiring to provide material support to terrorism.

Marquez made a brief appearance in U.S. District Court in Riverside following his arrest. He did not enter a plea. His court-appointed attorney, deputy federal public defender Young J. Kim, declined comment to a CNN producer outside court.

The information laid out in a 36-page affidavit by an FBI agent who investigated Marquez offers a chilling alternative view of the young man who many saw as a quiet nerd who tinkered with cars and read comic books.

The document describes a radicalization that took place under the noses of family, friends and neighbors, in which Farook allegedly transformed Marquez in a matter of years from a new convert to Islam to a would-be terrorist plotting a massacre at a community college and a “rush hour” pipe bomb and rifle attack on a Southern California freeway.

“Terrorist? Are you kidding me?” said Sharon Morgan, whose husband, Jerry, hired Marquez to check IDs at his bar, Morgan’s Tavern.

She described Marquez as a respectful, conscientious kid who loved oldies music, including “Close To You” by the Carpenters, which he would play on the jukebox.

Outwardly innocent but, affidavit says, privately plotting

Morgan, who was interviewed while Marquez was being questioned by the FBI but prior to charges being filed, said Marquez had come into the bar as a patron a couple of times and at one point got into a conversation with her husband. He ended up with the security job checking IDs at the front door on evenings when the bar offered live music.

She described him as a “Dudley Do-Right” character who took his job very seriously.

She recalled walking up to him the first time he worked security and finding him with an uncomfortable look on his face. When she asked what was wrong, he said he needed to go to the bathroom.

“Well, go. You don’t have to ask,” she said she told him.

Marquez replied: “I didn’t want to leave my post unattended.”

Fast facts: U.S. terrorist attacks

According to the affidavit filed in federal court on Thursday, Marquez in late 2011 began buying guns, ammunition and tactical gear in preparation for an attack. He and Farook even trained at local firing ranges, the court document states.

But during the next year, Marquez began to distance himself from Farook for various reasons, including some terrorism-related arrests that made headlines, the affidavit states.

But he clearly continued to think about his past association with Farook as he posted on Facebook a month before the attacks.

“My life turned ridiculous,” Marquez wrote, moments after writing that he was leading multiple lives.

“I think everyone leads multiple lives,” someone replied.

Marquez wrote of his life: “involved in terrorist plots, drugs, antisocial behavior, marriage, might go to prison for fraud, etc.”

Told 911 dispatcher he wanted to kill himself

Less than a month after that Facebook post, Farook and Malik opened fire at the Inland Regional Center, killing 14 people and wounding 22 with the AR-15 rifles Marquez allegedly bought for Farook.

The following day, Marquez called 911.

He told the operator he wanted to kill himself, the affidavit states.

When the operator asked why, he said Farook was responsible for the San Bernardino attack.

“The [expletive] [expletive] used my gun,” he said.

That same day, Marquez said, he downed about nine bottle of beer and showed up the UCLA Harbor Medical Center emergency room, according to the affidavit. He was referred to the psychiatric ward and placed on an involuntary hold.

In the wake of the attack, FBI agents spent days interviewing Marquez, though details about when and where those interviews took place are not made clear in the affidavit. The document says Marquez waived his right to an attorney during questioning, but a public defender has since been appointed to him.

Didn’t make a big impression in school

As news that Marquez was being questioned in connection with the attacks hit the media, a portrait of the young man began to emerge.

His mother, who declined a formal interview with CNN, at one point told a group of reporters gathered in front of the family home that her son was “a good boy.”

She said she knew nothing of the FBI’s interest in her son, whom she described as having been a normal teenager.

Others who crossed paths with Marquez during his formative years said he left little impression, other than being quiet and alone.

Several students who attended Alvord Continuation High School with Marquez in 2010 were able to identify his photo in the yearbook but could say little else about him.

“It was a very small school. Kids hung out in groups. Everybody had friends,” said one former student who asked not to be named. “He was always alone.”

Teachers at the school had similar recollections:

“I recognize him, but nothing really stands out,” said retired teacher Christine Van Houten. “I don’t even remember who he hung out with.”

A Walmart co-worker who was interviewed by FBI agents about Marquez following the attack said she told the agents she did not know Marquez well, didn’t spend time with him outside of work, and had never heard him talk about Farook or guns or terrorism. In a brief interview with CNN, she offered a theory on his possible involvement:

“He was weak-minded,” said the employee, who asked not to be named, “maybe he got suckered into something.”

’The last person on earth I would suspect’

Marquez seemed most memorable at Morgan’s Tavern, the bar where he worked in Riverside, about 20 miles from the site of the massacre.

Jerry Morgan said he thought Marquez felt a sense of belonging at the bar, even though no one knew him well.

For example, Morgan said, no one knew Marquez was married to woman whose sister was married to Farook’s brother – a marriage federal authorities now allege was a sham intended to secure a green card for the Russian national.

Jerry Morgan said Marquez always came to the bar alone, whether as a patron or an employee.

“I never seen him with a girl,” he said.

He said he never heard Marquez talk about terrorism or jihad or anything that would indicate his involvement – or even interest – in either.

“He would be the last person on earth I would suspect,” Jerry Morgan said days before charges were filed against Marquez. “If I would have had even of whiff of that I would have fired him and slapped him upside his head.”

Though Marquez worked a couple nights a month at the bar for years, Morgan said the relationship he had with him was superficial – an arm’s-length familiarity stemming from casual conversation.

“That’s how everybody knew Enrique,” Morgan said.

What are the charges against Marquez?

CNN’s Traci Tamura, Wes Bruer and Alberto Moya contributed to this report.