A U.S. citizen credited with helping online poker companies move billions of dollars in illegal gambling proceeds overseas from U.S. customers pleaded guilty Tuesday to conspiracy charges.

Ira Rubin, 53, entered the plea in U.S. District Court in Manhattan. Prosecutors say he made it appear that money processed by poker companies through U.S. banks was actually the proceeds of transactions on websites for golf stores, electronic companies or other businesses. Rubin admitted he created dozens of websites so that gambling proceeds could "be disguised as payments from non-existent online merchants." He said he carried out the fraud from 2006 until last March.

Rubin was swept up last year in a federal prosecution that shut down the three largest Internet poker companies operating in the United States and resulted in charges against 11 individuals.

He has been held without bail after he was arrested in Guatemala last April as he prepared to travel to Thailand. Authorities said he had lived in Costa Rica since 2008. He was facing charges that carried a potential sentence of more than 80 years in prison, but his guilty plea came with an agreement with prosecutors that the recommended sentence would be between 18 months and two years in prison.

He pleaded guilty to conspiracy charges related to illegal gambling, bank fraud, wire fraud and money laundering. He admitted that he helped Pokerstars, Full Tilt Poker and Absolute Poker hide the true nature of their transactions. Sentencing was set for May 17.

The plea came from a defendant who prosecutors had portrayed as a frequent offender, facing or having faced criminal charges in New York, Massachusetts, Missouri, Nevada, Florida and Virginia since the 1970s. They say he has yet to pay an $8 million Federal Trade Commission judgment against him because of a payment-processing business he operated from 2003 to 2006 that was tied to telemarketing fraud.