EVERETT – Prosecutors said the owner of a chain of Mexican restaurants in King and Snohomish counties used sales-suppression software to avoid paying $5.6 million in state taxes.

The Daily Herald reported that 57-year-old Salvador Sahagun, of Bothell, is facing felony theft charges filed this week in Snohomish County Superior Court. Charging papers say state employees went undercover at six Tacos Guaymas restaurants he operates in Marysville, Lynnwood and Seattle.

The state Attorney General’s Office says this is the second case it’s ever prosecuted involving such software, which can understate the revenues of a business by making some transactions appear to have been for less money or by making transactions disappear entirely.

No attorney has formally appeared in court on Sahagun’s behalf, and he did not appear to have a listed phone number. A woman who answered the phone at a Tacos Guaymas location in Seattle on Friday morning said he no longer owns that location.