The workers were identified after Immigration and Customs Enforcement agents audited recent hiring records of Phoenix Staffing LLC and found what the federal agency termed "discrepancies leading agents to believe that a number of the company's employees may not have been authorized to work in the United States."

Phoenix Staffing is a temporary employment agency used by Regal Logistics, an Immigration news release said.

Regal Logistics stores merchandise entering the United States from other countries, the agency added.

According to its Web site, Regal Logistics manages "warehousing, transportation and distribution for the toy, apparel, housewares and footwear industries."

Immigration agents said the majority of the unauthorized employees were from Mexico and it appeared many used counterfeit ID to obtain the jobs.

Wednesday's inspection was part of an effort to focus on businesses with ties to "security sensitive sites and critical infrastructure facilities" such as airports, military bases and customs warehouses. Unauthorized workers with access to such sites can be exploited by terrorists or smugglers, the agency news release said, noting Regal Logistics' facilities are close to major seaports, railyards and airports.

"When someone uses fraud or false documents to gain access to a major cargo hub like the Seattle-Tacoma area, we have no way of knowing who they really are or what their motives might be," said Leigh Winchell, Immigration special agent in charge in Seattle.

Neither Regal Logistics nor Phoenix Staffing immediately returned calls for comment placed after business hours Wednesday.

In the Southeast, federal immigration agents arrested 24 suspected illegal workers Wednesday at a Marine Corps base in North Carolina and at the Atlanta airport.

Agents arrested 21 illegal immigrants working for construction companies at Camp Lejeune Marine Corps Base, the agency said. The workers were from Guatemala, Honduras, El Salvador and Mexico and most had counterfeit immigration documents.

In Atlanta, two people from Senegal and one from Mexico were arrested at Hartsfield International Airport, where they had identity badges for access to secure areas. The arrests followed checks of records of employees at Le Petit Bistro in the airport, immigration authorities said.