In online poker circles, they’re calling it Black Friday: On April 15, the federal government shut down several major online poker sites, filing criminal charges against the operators and cutting off the cash flow of those who were playing online poker for a living.

The U.S. Attorney’s Office in Manhattan says the three leading sites among U.S. users tried to trick their way around a ban that prevents U.S. banks from processing payments for offshore virtual gambling halls. Authorities charged 11 executives, including the founders of Ireland’s FullTiltPoker.com, Costa Rica’s AbsolutePoker.com, and PokerStars.com, based on the Isle of Mann, with bank fraud, money laundering, and illegal gambling. Prosecutors say that the poker companies fooled some banks and bribed others to keep the money flowing.

The charging documents name two principals from each company, plus others who allegedly worked with them to illegally process payments.

The Internet poker market in the U.S. was $5.1 billion last year, 7.1 percent higher than 2009, and the global market is about $30 billion, according to Bloomberg, which cites data from U.K.-based H2 Gambling Capital.

Now, though, U.S. users who try to access the three shuttered sites will find themselves looking at two Department of Justice seals, explaining that the domain names have been seized. H2 Gambling, the data company that has been tracking the fallout since Friday, noted on Sunday that PokerStars' player traffic was down 26 percent, FullTilt’s fell 50 percent, and Absolute Poker's dropped 40 percent.

Meanwhile, other gambling sites that continue to service the U.S. market appear to be beneficiaries of the shutdown, confirming the claims of disappointed poker players who said their games would simply shift to new locations.

According to H2 Gambling data, Merge Poker, Bodog, and the Cake Poker Network are seeing increases in traffic of between 10 and 30 percent since their rivals closed shop.

Meanwhile, those in the U.S. who have actually quit their jobs to play poker online now have thousands of dollars tied up in accounts that they can no longer access.

One, who would only give his first name, Mike, told KLAS-TV 8 in Las Vegas that he quit his job as an accountant and that for the past six years, his online poker winnings have become his primary source of income.

"I was able to purchase a second house that I would never have been able to purchase on a salary of an accountant," he said.

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