A 24-year-old Wal-Mart security guard, known to friends as a shy cycling enthusiast who wanted to join the military, has emerged as a key figure in last week's terror attack at a San Bernardino social services center.
Enrique Marquez Jr. purchased two military-style rifles several years ago that Syed Rizwan Farook and Tashfeen Malik used in the attack that killed 14 people at the Inland Regional Center, according to federal authorities.
Marquez has cooperated with FBI agents, who have been interviewing him in recent days, according to a law enforcement source speaking on the condition of anonymity. He purchased the weapons in 2011 or 2012, around the time Farook is believed to have begun considering carrying out a terrorist attack in the U.S., according to a federal government official who also spoke on condition of anonymity because the investigation is ongoing.
There is no paperwork transferring ownership of the weapons to Farook, federal officials have previously said.
Farook told at least one associate about his plans, according to a source, but it was not clear to whom he spoke. Marquez also converted to Islam around the time Farook began to consider an attack, the source said. Members of the Islamic center where Marquez sometimes attended prayer, however, said his presence at the mosque was uncommon.
Marquez lived next door to Farook on Tomlinson Avenue in Riverside for many years. Neighbors said they were good friends who often worked on old cars together. He also cemented his connection to his next-door neighbor by marrying the sister of Farook's sister-in-law last year, according to county records.
The circumstances of the marriage are now also under investigation, according to a federal official who spoke on condition of anonymity because the probe is ongoing.
Marquez's relationship with Farook and his purchase of the weapons have become focal points of the investigation into the deadliest terror attack on U.S. soil since Sept. 11, 2001.
Hours after the deadly attacks in San Bernardino, a cryptic message was posted on Marquez's Facebook page.
"I'm. Very sorry sguys (sic)," it read. "It was a pleasure."
Marquez checked himself into a mental health facility following the attacks. Federal agents searched his home and seized several items. Attempts by The Times to contact Marquez were unsuccessful.
Viviana Ramirez, 23, a friend of Marquez's and fellow student at Riverside City College, described him as shy but said they bonded over their mutual desire to enlist in the military. Marquez, she said, rarely spoke about his family or his marriage but could become playful, even silly, once he dropped his guard.
"He has a really nice smile, he's really welcoming," she said. "He'll play around if he feels very welcome with you."
Marquez purchased the weapons at least three years ago, federal officials have said. It is not clear when he gave them to Farook.
Marquez never spoke of Farook, according to Ramirez. He talked most often about his desire to enlist in the U.S. Navy. He was intensely focused on that goal and physical fitness, choosing to ride his bicycle to and from work, she said.
But Marquez's ambition was accompanied by occasional admissions of sadness or loneliness, according to Ramirez. He would sometimes publish melancholy or depressing posts on Facebook, Ramirez said, even though his page was otherwise littered with pictures of Marquez smiling or making clownish faces while wearing a bicycle helmet.
On one of the few occasions that he opened up about his personal life, Ramirez remembers Marquez confessing that he and his new wife were "not clicking."
Marquez married Mariya Chernykh in November 2014, according to county records. The marriage added another connection to the Farook family; Chernykh's sister was married to Syed Raheel Farook, the shooter's older brother.
The sisters are from Russia, according to marriage records. Raheel and his wife were both witnesses at Marquez's wedding, records show. Raheel and Chernykh's sister, Tatiana Gigliotti, were married in 2011.
The women came to the United States separately on J-1 visas, which allow foreign individuals to enter for work-study cultural exchange programs, according to the federal official who spoke on the condition of anonymity.
Marquez's marriage could strike some people as odd, although Ramirez did not find it unusual. Marquez did not live with his wife, she said, and he never explained his living arrangements.
"He never really talked about the friends he had. He wouldn't bring anybody up," Ramirez said. "He was more of an in-the-moment person."
Brittani Adams, a neighbor of Syed Raheel Farook, said she had seen Marquez and Chernykh around the family home but the two looked like anything but a married couple.
"He would never leave with her, come with her, not hug her," Adams, 24, said. "None of them seemed like they were married. It was very weird."
A Wal-Mart spokesman said Wednesday that Marquez had worked for the retail giant since May but that the company has made the decision to fire him. He did not elaborate.
A spokesman for the Riverside Community College District said that Marquez began attending classes at Riverside City College in the fall of 2009. Marquez withdrew after the winter term of 2011, around the time he purchased the weapons used by Farook.
The spokesman could not provide further details regarding Marquez's studies.
Marquez attended prayers at the Islamic Society of Corona-Norco four or five years ago, though not regularly, according to Yousuf Bhaghani, president of the facility's board of directors.
"We have members who actually are recognized in writing and everything, and then you have people who come and go," Bhaghani said. "Enrique was one of those guys who used to come, but he was not a permanent member."
Authorities have not contacted the Islamic Society about Marquez, said Bhaghani, who did not know when Marquez converted to Islam.
"We're trying to figure out how he got converted. Who converted him?" he asked. "Because obviously he's Hispanic and converted Muslim. So far, we really don't have much to go with because the people who remember him, remember that he used to come and pray but that's pretty much it."
It was not clear if Farook had also attended the center at any point.
Ramirez said she sent Marquez a message on Facebook to check on him in the days after the massacre, but he did not respond.
Despite Marquez's links to the terror suspects, Ramirez said she doubts he would have done anything to help Farook and Malik if he knew what they had intended to do with the weapons.
Ramirez is hosting a Christmas party this weekend and said she would still gladly welcome Marquez into her home.
"He's never done anything mean. A lot of newspapers call me and want me to talk bad about him," she said. "He is a really good person."
Staff writers Jack Dolan, Zahira Torres and Paloma Esquivel contributed to this report.
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