On December 2, 2015, a man named Syed Rizwan Farook and his wife, Tashfeen Malik, opened fire on employees of the Department of Public Health in San Bernardino, California, killing 14 people and injuring 22 during what was supposed to be a staff meeting and holiday celebration. The shooters were tracked down and killed later in the day, and FBI agents wasted no time trying to understand the motivations of Farook and to get the fullest possible sense of his contacts and his network.

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