About 1,000 nonunion workers, mostly Hispanics upset with the recent firing of immigrants for allegedly providing false documents, walked off their jobs at a Smithfield Foods Inc. slaughtering plant, a union spokeswoman said.

About 300 workers were protesting Friday morning outside the plant, said Libby Manly, a representative of the United Food and Commercial Workers Union, which helped organize the protest and has been trying for years to form a union at the plant. The plant is considered the world's largest hog slaughtering plant.

Smithfield Foods also has failed to address problems of sexual harassment and denial of workers compensation claims, said Gene Bruskin, a representative of the union who serves as the Smithfield campaign director.

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"There's a long train of abuses in that plant really going back more than a dozen years," Bruskin said. "Recently the activity in the plant has been increasing."

Smithfield spokesman Dennis Pittman said the company was only complying with a request from U.S. Immigration and Customs Enforcement to gather the names, Social Security numbers, dates of birth and gender of workers at the plant. About 600 workers were found to have unverifiable information. The company fired about 75 people for providing false information, he said.

"This walkout — which apparently was instigated by the United Food and Commercial Workers Union — is totally unjustified," Pittman said. "If Smithfield were to do what the union is calling for, we would be breaking federal law by knowingly employing undocumented workers. The union should stop trying to pressure Smithfield to break the law."

Workers on Friday distributed a statement from Latino and black leaders that calls for an end to "unjust firing of Smithfield workers and the timely rehire of all workers who have been unfairly terminated." The statement also demanded no retaliation against protesting workers.

The plant, about 25 miles south of Fayetteville, employees 5,000 workers and slaughters up to 34,000 hogs a day. Smithfield, Va.-based Smithfield Foods is the world's largest pork processor.

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