FBI agents raided the Riverside, California, home of a friend of San Bernardino shooter Syed Farook early on Dec. 5. The friend is believed to have purchased two military-grade rifles used in the attacks on Dec. 2. The agency wants to determine whether or not the man had knowledge of the plans carried out by Farook and his wife, Tafsheen Malik.
The man, 29-year-old Enrique Marquez, has not been charged with a crime and reportedly checked himself into a mental health facility after the shootings.
Neighbors of Marquez and Farook told The Washington Post the two men had a common interest in cars, and could sometimes be seen working on them together.
Freddy Escamilla, 21, lived in the neighborhood for most of his life and told The Washington Post that "they had a common interest in mechanics and cars."
“They would walk over to each other’s yards to talk to each other. It never seemed out of the ordinary," Escamilla said.
Another neighbor, Lorena Agurre, told the Daily Mail Marquez and Farook were similar in that they were generally reserved, quiet and shy. She also corroborated the mutual interest in cars that the two men shared.
"He didn’t socialize much with the kids nearby. The only person I ever saw him with was Syed but I never spoke to them when they were together," Agurre told the Daily Mail.
Other accounts from local residents seemed to give a similar picture of the two men and their friendship. He was seen as somebody who liked to keep to himself and was described as a "nerd" and a "weirdo."
A neighbor told the Daily Mail that two people exited the house when the FBI conducted an overnight raid on Dec. 5.
"I saw two guys come out walking backwards with their hands on their heads. The police had them outside and asked if any explosives were inside the house. They said no, so then I saw the police use a saw to break into the garage and put some sort of robot thing inside."
ABC 7 reports that the main focus of law enforcement in the investigation into the shootings has increasingly centered around Farook's wife, Malik, and the question of whether or not she radicalized Farook.