FORT ATKINSON, Wis. (CBS 58) -- A Fort Atkinson accountant has been charged with four felonies for filing false income tax returns with fraudulent claims for credit and one felony charge for theft of customers' tax refunds.

According to the criminal complaint, David Zehnder ran tax preparation firm A-Z Productivity, Inc. The complaint alleges that from 2013 to 2017 Zehnder prepared and filed at least 83 fraudulent federal and Wisconsin income tax returns and, on many of those returns, he falsified the itemized deduction credits in order to increase customer refunds.

The complaint also alleges that as part of the scheme, Zehnder stole, or attempted to steal, $32,312 of his customers' refunds.

If convicted, Zehnder could face up to 34 years in prison, a $65,000 fine, or both.