POSTVILLE, Iowa (AP) - Immigration officials are raiding the Agriprocessors Inc. plant in the northeast Iowa town of Postville.

Agents with U.S. Immigration and Customs Enforcement on Monday issued criminal search warrants for aggravated identify theft and fraudulent Social Security numbers.

Agency spokesman Tim Counts told the Waterloo-Cedar Falls Courier that civil search warrants also were issued for illegal immigrants, and agents and medical professionals are evaluating those who have been arrested.

Several vehicles from the immigration agency and at least eight Iowa State Patrol cars and vans are at the plant. A helicopter is also hovering.

Agriprocessors is the world's largest kosher meatpacking plant.

A telephone call by The Associated Press to the plant went unanswered. A call to immigration officials wasn't immediately returned, while the phone was repeatedly busy at the U.S. attorney's office in Cedar Rapids.