A Sheboygan tax preparer who helped thousands of undocumented immigrants claim millions in illegal tax refunds has been sentenced to two years in federal prison, plus another year of supervision.

Lesley E. Anzures, 35, who operated Lesley's Tax Service on 8th St. in downtown Sheboygan, was charged in February. She later pleaded guilty to a single count of structuring a financial transaction.

But prosecutors portrayed Anzures' business as a veritable high-speed assembly line of fraud, churning out tax returns at a rate of more than one every hour of every working day over a four-year period.

As part of the plea deal, prosecutors recommended the maximum prison term of three years, and Anzures will be ordered to pay restitution of $496,533. U.S. District Judge Pamela Pepper on Tuesday imposed a two-year prison term, noting Anzures' lack of criminal history and her community involvement.

The IRS began an undercover investigation of Anzures after one of her customers complained to Sheboygan police that identifying information of the customer's child had been used in someone else's tax return.

Agents reviewed 40 tax returns Anzures had prepared for 12 clients over four years and found false claims in all of them, mostly for Additional Child Tax Credit, for children who did not exist or were not in the United States. An audit of another 22 clients' returns found more fraud, for a total tax loss of nearly $500,000 over the tax years 2010 through 2013.

"Even an undocumented immigrant customer fluent in English would find the tax system hard to comprehend. As such, these clients relied on her to accurately and fully tell them the relevant rules, to enable them to provide the necessary information to complete a tax return," federal prosecutors wrote in a sentencing memorandum.

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They also weren't buying Anzures' claims to have just relied on what her clients told her, and that she was only trying to help them.

"Casting herself as selflessly helping deserving people is a portrayal lacking support from the investigation findings, which suggest instead that she acted to enrich herself," prosecutors wrote.

For the four years in question, Anzures filed 9,489 returns, 98% of which claimed refunds totaling $34.2 million. Seventy percent of the dependents claimed on the returns had Individual Tax Identification Numbers used by undocumented immigrants who don't have Social Security numbers.

Prosecutors estimated that Anzures, based on her average fee of $75, made about $150,000 a year those four years. By the time she was 35, Anzures had acquired a $350,000 home, two late model Cadillacs, two rental properties and an auto business, while reporting adjusted gross incomes, with her husband, of $18,000 to $70,000. She also cheated on her own income taxes, according to the memorandum.

Anzures' online business profile indicates she has run the tax business since 2007 and also owns a grocery business in Sheboygan.

Anzures was granted permission to leave Wisconsin in June for a vacation in Orlando, Fla., with her husband and children.