Border Patrol agents working in Southern Arizona arrested a U.S. citizen for allegedly smuggling a group of illegal immigrants. The alleged smuggler identified himself as a member of the Sureños street gang out of California.

Casa Grande Station agents stopped a Ford Fusion on State Route 86 for an immigration inspection. During the interview, the agents learned the driver was a U.S. citizen currently residing in Phoenix, Arizona, according to Tucson Sector Border Patrol officials.

The interview revealed the driver’s five passengers were all illegal immigrants. The migrants came to the U.S. from Mexico and Guatemala. Three of the men and one woman came from Mexico while the fifth was from Guatemala, officials stated.

The driver reportedly admitted to Border Patrol agents that he is a member of the violent California-based Sureños street gang.

In 2014, authorities in California referred to the Sureños as one of the state’s most dangerous gangs, IBTTimes reported. The gang’s roots trace back to the late 1960s when factions of Hispanic gangs in southern California were forced to pay “tribute” to the Mexican mafia.

The news outlet reported:

The gang, which is said to be recruiting new blood at its fastest rate ever, specializes in murder, extortion and drug trafficking – leaving a trail of bloodshed across California in its wake. It has risen from a California-based operation to having tentacles stretching the length and breadth of America. Heavily tatooed, inherently racist and armed to the teeth, Sureños, which in Spanish means ‘south’, consists almost exclusively of Hispanic Americans and has fought a deadly long-running street war against a long list of rivals: Norteños, Nuestra Familia, Fresno Bulldogs, Bloods, Latin Kings, Puro Tango Blast, Los Zetas, and the Asian Boyz.

Since that time, MS-13 has come on the scene.

The five illegal immigrants are being processed for immigration violations according to Tucson Sector guidelines, officials stated. The U.S. citizen driver faces possible charges for human smuggling.