CHATTANOOGA, Tenn. (AP) -- A federal judge granted class-action status to a lawsuit that contends Tyson Foods Inc., the world's largest meat producer, depressed wages by hiring illegal immigrants at eight plants in Tennessee, Alabama, Indiana, Missouri, Texas and Virginia. 
   

 Howard W. Foster of Chicago, an attorney for Tyson employees, described the ruling as a "very big step," allowing him to seek damages for thousands of workers at the eight plants instead of just the four original plaintiffs.
   

 Roger Dickson of Chattanooga, an attorney for the Springdale, Ark., company, said he had not had a chance to read the judge's order and declined further comment.
   

 "This is a procedural ruling and not based on the merits of this case, which was actually dismissed by another judge back in 2002," Tyson spokesman Gary Mickelson said. "We remain confident our company will ultimately prevail."