"Acquaintance Enrique Marquez had given the couple the semiautomatic Smith & Wesson M&P15 and .223-caliber DPMS A-15 rifles, authorities said. Until a few months ago, Farook and Malik lived in Riverside, next door to Marquez. Farook, observed as quiet and withdrawn, struck up a friendship with Marquez, who shared a similar interest in tinkering with cars, a neighbor recalled. Federal authorities interviewed Marquez over the weekend, and a law enforcement official familiar with the investigation said the weapons he gave to Farook were legally purchased in 2011 and 2012. There is no paperwork of them being transferred to Farook, he said."