U.S. immigration officials have launched raids at several Mississippi food processing plants.

A U.S. Immigration and Customs Enforcement official said Wednesday that search warrants were executed at seven locations across the state targeting several companies. They include the Morton plant of poultry producer Koch Foods Inc., which has no relation to Charles and David Koch.

The official spoke to The Associated Press on condition of anonymity because details of the operation were not intended for publication.

The official says owners as well as employees are targeted in a federal criminal investigation.

The AP witnessed dozens of agents ready to process the workers inside a military facility in Flowood, Miss., with seven lines, one for each location.