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.

Read the article “The Muslim Convert Who Bought the Rifles Used in the San Bernardino Shooting: Who is Enrique Marquez?” on latimes.com.