An alleged member of one of the most violent Mexican drug cartels was found in an American sanctuary city and turned over to Mexican officials on Tuesday.

Coahuila state police officers traveled to the Mexican border city of Nuevo Laredo where they took custody of Juan Rafael “El Cubano” Arredondo Oviedo.

U.S. authorities arrested Arredondo, a “foot soldier” in the Los Zetas Mexican drug cartel, at an immigration court in Chicago, Illinois, a sanctuary city, where he sought to be a protected as a witness from the Los Zetas cartel who he said is going to kill him.

Arredondo, who faces 28 kidnapping charges in Mexico, is linked to a horrific 2011 massacre in Coahuila, Mexico, where estimates say over 300 people were kidnapped, murdered, and incinerated in ovens.

The Los Zetas cartel is considered one of the most violent drug cartels in Mexico and operating out of the eastern part of the country from the Texas-Mexico border all the way south to the Guatemala-Mexico border.

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