The Maricopa County Sheriff's Office says 11 people have been arrested in an operation targeting false identifications used to gain employment.
Sheriff's officials say three locations of the America's Taco Shop were targeted Thursday afternoon.
Two of the restaurants are in Phoenix and the other in Tempe.
MCSO says the restaurant chain has been under investigation for more than a year.
Investigators say 16 workers were identified as using false identities and Social Security numbers.
Four of the 11 arrested Thursday were booked into jail on suspicion of identity theft and forgery.
Sheriff's officials say the other seven arrested were turned over to federal immigration authorities for "border violations issues."
MCSO says it was their 72nd workplace identity theft operation.