The nerd-next-door who supplied guns to killer couple Syed Farook and Tashfeen Malik was a recent convert to Islam!
That's the troubling charge emerging from the FBI's initial conversations with geeky neighbor Enrique Marquez, who quickly committed himself to a mental hospital after his pals shot up in the Inland Regional Center for people with developmental disabilities in San Bernardino, Calif.
Farook's longtime pal has already admitted to supplying the deadly duo with the two "assault-style" rifles used in the deadly attack that killed 14 people and wounded 22 more.
The rifles had been illegally modified to fire automatically and use high-capacity magazines to create a higher kill count for the husband-and-wife terrorists.
Marquez, 24, and 28-year-old Farook had spent years living alongside each other in Riverside, Calif.
Records show that Marquez had purchased the original rifles in late 2011 and early in 2012. Those purchases were very close to the time when Farook brought two handguns that would also be used in the deadly attack.
Authorities are now further alarmed by reports from ABC News that Marquez had also converted to Islam, with a member of a local mosque telling reporters that he had become a regular at the house of worship.
Meanwhile, police are also trying to track down the source of a mysterious $28,500 payoff made to Farook's bank account.
"It could just be a loan that he had applied for expecting to soon die in a suicide mission," an FBI insider told The ENQUIRER.
"But authorities also have to look into the possibility that they were being financed by an ISIS sleeper cell in America.
"And it's become very troubling that Farook gave a lot of that money to his mother!"
Officials developed new concerns about Farook's mother, Rafia Farook, after a sticker at his home showed that his mom had a connection to a controversial mosque in New York City.
Investigators also confirmed that Rafia was living in the same house where her son and her radicalized daughter-in-law built up a massive stash of weaponry and pipe bombs.
The psycho killers had left their 6-month-old daughter with Rafia before beginning their deadly siege on the Inland Regional complex.
Family attorney David Chesley has insisted that Rafia knew nothing of the massacre — but her ex-husband, also named Syed Farook, told an Italian newspaper that he knew his son had developed extremist political beliefs.
An FBI spokesman told reporters that the agency was not "prepared to discuss Mr. Marquez at this point" — but FBI Director James Comey said that agents are discovering "a lot of evidence that doesn't quite make sense!"
