SAN FRANCISCO—In coordinated raids Monday at locations in Delaware, South Dakota, and California, federal agents apprehended dozens of executives at Visa Inc., a sham corporation accused of perpetrating the largest credit card scam in U.S. history.

According to indictments filed in U.S. District Court, Visa posed as a reputable lender, working through banks to peddle a variety of convincing-looking credit cards carefully designed to dupe consumers into spending far more money than they had. The criminal group would then impose a succession of escalating fees on unpaid balances, allegedly bilking some $300 billion from victims in the past year alone.

"This is criminal behavior of the most vile sort," Attorney General Eric Holder said in a press conference following the arrests, estimating that one in three Americans have fallen for the scam since its inception in the 1970s. "By masquerading as a legitimate business, this illicit syndicate was able to prey on helpless citizens for decades, charging unfathomable interest rates on the order of 15, 20, even 30 percent or more. It's staggering. Nobody could afford that."

"The actions of the Visa crime ring amount to nothing less than mass extortion," Holder continued. "Anyone who's holding a Visa card has most likely already been ripped off."

Calling the scam's breadth and sophistication "unparalleled," Holder said the ringleaders of the plot carefully portrayed themselves as top-level financial executives, spent untold sums of victims' money on a luxurious high-rise headquarters in San Francisco, and employed scores of graduates from elite business schools—all as a means to perpetuate an elaborate confidence game.

Investigators said Visa often targeted vulnerable individuals, such as those with limited financial resources, students, and even the elderly. The group's typical con involved direct solicitation through letters supposedly written by the CEO himself, which often praised the recipients by name and stated that they had been hand-selected for favored treatment.

"I needed to pay off some medical bills, and this seemed like a good option," said Visa cardholder Eileen Carlson of Phoenix, explaining that her initial skepticism of the offers was worn down by the barrage of official-looking mail she received almost daily from the criminal organization. "But before I knew it, they were demanding at least $900 a month, which I couldn't pay. They knew I didn't have any money to begin with—what did they expect?"

"And they kept after me for years," added Carlson, breaking into tears. "For christsakes, you can't get blood from a stone."

According to the Federal Trade Commission, Visa often employed perverse twists on its standard ruse, luring victims with promises of free gifts, enticing but inscrutable "rewards" programs, or deceptively low interest rates that later ballooned out of control and siphoned away every last penny a person had.

"These crooks manipulated interest rates and charged arbitrary, exorbitant fees on literally anything they could—too much credit card activity, too little activity—it was utterly shameless," said Barbara Pendleton of the FTC, suggesting Visa used deliberately confusing financial language as well as fraudulent threats of litigation to squeeze money from its victims. "Then they sat back and did nothing while the money flowed in from people who actually work for a living."

Added Pendleton: "What's more—and this is truly sickening—they became so confident they could get away with this stuff that they openly conducted national ad campaigns and sponsored charity events. These people are the scum of the earth."

According to former Visa CFO R. Neil Williams, a crime boss turned government informant, the syndicate compiled troves of sensitive personal data on millions of Americans, including home addresses, birth dates, and income levels, and regularly sold this information to third parties or exploited it to draw new victims into the scam.

"Sure, people should have known better than to trust a magical card that allowed them to buy anything they want without any money whatsoever," Williams said. "But at Visa we understood that people will believe anything if they want it bad enough. That was the genius of our whole scheme."

As of press time, lawyers for Visa had proclaimed their clients' innocence, citing the fact that there is still no federal law stopping banks from charging any interest rate they goddamn please.