A member of the notorious MS-13 gang, known in the streets as “Casper,” has received a sentence of over five years for unlawful ammunition possession in the San Francisco Mission District. Christian Quintanilla, 24, from San Pablo, faced the music at the hands of Chief United States District Judge Richard Seeborg, confirmed by First Assistant United States Attorney Patrick D. Robbins and Homeland Security Investigations Special Agent in Charge Tatum King, according to the U.S. Attorney’s Office.