A federal sweep targeting unlawful immigrants has led to the arrest of several people who have been charged with being in the country illegally.

One of them, Walter Cruz Sanchez-Armira, 24, has been charged with being in the United States after having been previously removed from the country, according to the U.S. Attorney’s Office.

Prosecutors say Sanchez-Armira is a Mexican citizen who was encountered by authorities conducting a search warrant at the Twin Super Buffet in Brewer and an associated residence.

Earlier this week, federal officials and local police agencies executed nine search warrants at four Chinese restaurants, including one in Lewiston where illegal aliens had allegedly been employed. They also searched and five “safe houses” where the illegal aliens were alleged to have been residing, prosecutors said.

In addition to Sanchez-Armira, nine men were administratively arrested for being illegally present in the United States. Three are from Guatemala, prosecutors said. Others are from China, Mexico and Honduras.

Agents said they also encountered an additional 13 employees who had no authorization to work in the United States.

Prosecutors from the U.S. Attorney’s Office on Friday did not say if any of those charged were found during a Wednesday afternoon raid at a Lewiston restaurant.

Lewiston police along with several armed federal agents swarmed on the New China Super Buffet at the Lewiston Mall on East Avenue. The raid was conducted simultaneously with the one in Brewer during which Sanchez-Armira was arrested.

The investigation is being conducted by the Immigration & Customs Enforcement-Homeland Security Investigations, Department of Homeland Security, with the assistance of the Department of Labor-Office of Inspector General.