ARLINGTON, Wash. -- An immigration raid at an Arlington aircraft parts plant resulted in the arrest of 32 workers on suspicion of immigration violations.

The U.S. Immigration and Customs Enforcement (ICE) agents executed a federal civil search warrant Thursday morning at Arlington’s Aerospace Manufacturing Technologies, Inc. (AMT).

AMT is a leading supplier of frame and interior parts for commercial and military aircrafts. They even provide parts used in Boeing’s 737 and 777.

The unauthorized workers included foreign nationals from two countries. The group including 16 men and 16 women are from two different countries. Thirty of them are from Mexico and two are from El Salvador, said ICE.

Chief Executive Officer of AMT, Jerry Goodwin, said those arrested were good, hardworking people. Some of them had been at AMT for 10 to 15 years.

ICE said agents conducted the raid after they audited AMT employment records and found discrepancies which led them to believe a small percentage of the company’s employees used counterfeit documents to secure their jobs.

"We have no way to prove or disprove falsification of documents," said Goodwin.

Investigators said there is no evidence that AMT was aware that some of the workers used false credentials to secure their employment.

"We had no idea that they were not legal," said Goodwin.

ICE agents said those arrested are being interviewed and processed for removal from the United States.

Based on information during the interviews, ICE has released four women on humanitarian grounds, pending further immigration investigations. The remaining 28 workers in custody will be held at the Northwest Detention Center in Tacoma.

Agents continue to investigate.

ICE has set up a local phone number family members of the arrested workers can call with questions about their relative's detention status and the removal process. The phone number is: 206-553-5657.