The Mexican Mafia (Spanish: Mafia Mexicana [ma'fia mexi'kana]), also known as La eMe (Spanish for the letter M), is a Mexican American highly-organized, criminal organization in the United States.[1][4] Despite its name, the Mexican Mafia did not originate in Mexico and is entirely a U.S. criminal prison organization. Sureños, including MS-13 and Florencia 13,[16] use the number 13 to show allegiance to the Mexican Mafia. M is the 13th letter of the alphabet. Law enforcement officials report that La eMe is the most powerful gang within the California prison system.[17] Government officials state that there are currently 155--300 official members of the Mexican Mafia with around 990 associates who assist La eMe in carrying out its illegal activities in the hopes of becoming full members.