In an apparent crackdown on illegal immigrants that may signal more to come, Cintas, the large uniform manufacturer, placed six employees from its San Jose plant on unpaid leave Monday. The move came after the workers failed to verify their Social Security numbers, a document required by employers to prove their workers have the right to be employed in the United States. About 60 Cintas workers, labor organizers and immigrant advocates, rallying outside the East San Jose plant Monday afternoon, denounced the action. With 30,000 workers in five states, Cintas, is believed to be the first company in the country...