OAKLAND — At last Monday night’s Oakland Raiders football game, U.S. Immigrations and Customs Enforcement — best known for targeting undocumented immigrants — turned its attention toward counterfeit sports gear instead.

The agency’s Homeland Security Investigations unit confiscated nearly $11,000 worth of fake merchandise, according to a news release.

“HSI San Francisco is committed to conducting intellectual property theft investigations throughout the year, and preventing the sale of counterfeit goods during the home opener of the Oakland Raiders is just one example of HSI working to ensure that the public is purchasing legitimate products,” Tatum King, special agent in charge of HSI San Francisco and Northern California, said in a statement.

The fakes, which often contain substandard materials, mean lost revenue and lost jobs for authorized manufacturers, King said.

ICE urged fans to shop at official team stores and to keep an eye out for ripped tags or irregular markings.

“Oakland Raiders fans attending the first game of the season deserve genuine products and the proceeds of counterfeit merchandise ends up in the hands of transnational criminal organizations engaged in varying types of illegal activities,” King said.

The operation was conducted in partnership with NFL brand security representatives and state and local law enforcement officers, according to the release. The Oakland Police Department said it was not involved.

Harry Harris contributed to this report.