were first neighbors. this woe grow up to become friends, then relatives by marriage. did he seem like a relative? yeah, i could sense that. he was really close with them. it wasn t just, like, a friend that you would see over. reporter: brittany dane lives two doors down from the home where farouk s father, brother and sister-in-law live. dane saw marquez frequently here. the home not far from this mosque, the islamic society of corona nor co-. members of the mosque tell cnn several years ago, marquez came here alone, saying he had cop verted to islam, but he only attended a handful of times. this is a mosque marquez listed on his december 2014 marriage certificate as his religious institution. his wife is the sister of the woman married to syed rizwan farook s brother. but to outsider, the marquez s marriage seemed unusual. it wasn t like they were married or anything, like he helped them, but it wasn t like
he i didn t really see him give much, like he didn t talk much to the sister. reporter: marquez tells authorities he didn t know about the sbar massacre and is currently not charged with a crime but his role remains crucial to investigators. we are also working very hard to understand whether this there was anybody else involved with assisting them, with supporting them, with equipping them and we are working very, very hard to understand, did they have other plans, either for that day or earlier? reporter: now, u.s. off uses who have been talking to marquez, who got that claim about the 2012 terror plot, well, they are actually cautiousing us also, too, that they have to verify it, they need to make sure that s not just making it up. there is some concern that he could be saying that to try to deflect from the fact that he did purchase those two long guns that would be used in the massacre. erin, we should point out that shortly after the attack, marquez did initially check
interest end who supplied the assault rifles to the massacre killer helped the terrorist, sayyid rez juan farouk plot an attack in 2012. his name is enrique marquez. who is he? reporter: investigators focusing on enrique marquez and not just for buying the two high-powered a r-15 rifles that would be used in the sbar massacre. officials telling cnn marquez told investigators about a 2012 attack that answered farouk hatched but did not carry out. they abandoned the plan, marquez told them, because they got spooked much the fbi had just arrested four people in the area accused of trying to travel abroad to carry out violent jihad. marquez also telling investigators he and farouk were both on the path to radicalization as early as 2011, the same year he bought the first of two rifles for farouk. the two men s lives have been connected for years. syed rizwan farook and marquez