In a case highlighting the infiltration of the Transportation Security Administration (TSA) by transnational criminal organizations, twelve current and former TSA officers and airport staff were indicted for allegedly trafficking over 20 tons of cocaine — worth over $100 million — into the U.S. over a 28-year time frame.

Last Wednesday, a federal grand jury returned an indictment against the twelve defendants, who are charged with conspiracy to possess with intent to distribute cocaine.

From 1988 to 2016 the conspirators allegedly smuggled about 40,000 pounds, or twenty tons, of cocaine through Luis Muñoz Marín International Airport in San Juan, Puerto Rico, and into the United States, according to the DOJ.

The DOJ press release detailed how the massive trafficking operation allegedly worked:

During the course of the conspiracy, the defendants smuggled suitcases, each containing at least 8 to 15 kilograms of cocaine, through the TSA security system at the Luis Muñoz Marín International Airport (LMMIA). Sometimes as many as five mules were used on each flight, with each mule checking-in up to two suitcases. From 1998 through 2016, the defendants helped smuggle approximately 20 tons of cocaine through LMMIA.