U.S. Immigration and Customs Enforcement agents serve an employment audit notice at a 7-Eleven convenience store Wednesday, Jan. 10, 2018, in Los Angeles. Agents said they targeted about 100 7-Eleven stores nationwide Wednesday to open employment audits and interview workers. 

(AP Photo/Chris Carlson)

Federal immigration officials say six Denver area 7-Eleven stores were part of a nationwide sweep Thursday morning to find undocumented immigrants working illegally in the United States.

U.S. Immigration and Customs Enforcement agents targeted 98 7-Eleven stores in 16 other states and the District of Columbia, the Department of Homeland Security said. It was the biggest private employer immigration sweep to date under President Donald Trump.

Immigration officials say the raids aim to ensure companies are hiring employees responsibly. There were no arrests in the Denver area.

“Today’s actions send a strong message to U.S. businesses that hire and employ an illegal workforce: ICE will enforce the law, and if you are found to be breaking the law, you will be held accountable,” said ICE Deputy Director Thomas D. Homan in a statement. “Businesses that hire illegal workers are a pull factor for illegal immigration and we are working hard to remove this magnet” and protect jobs for American workers.

This is part of a more stringent approach to illegal immigration that resulted in twice as many deportations from Colorado and Wyoming in the last fiscal year, in 2017, than under President Obama. All workers found during these sweeps who are not legally working in the United states are subject to arrest and their employer faces fines.