In a sign of the continuing crackdown on H-1B visa fraud, a Sunnyvale man has been indicted by a federal grand jury for an alleged scheme to illegally bring in 600 foreign workers to Silicon Valley over the past decade.

Kishore Kumar Kavuru, 46, billed himself as a “staffing specialist” for technology firms looking for skilled foreign workers to fill temporary positions. Instead of employers properly filing applications for workers to fill real jobs, however, Kavuru is accused of using his four consulting companies to file fraudulent applications for non-existent jobs.

“Because many of the applications were ultimately approved, Kavuru had a pool of unemployed H-1B beneficiaries that were immediately available for legitimate work projects,” according to the U.S. Department of Justice, “giving him a competitive advantage over other law-abiding staffing companies that followed the sometimes lengthy visa application process for petitioning foreign workers.”

Attempts to reach Kavuru by phone and email on Saturday were not immediately successful.

As part of the scheme, according to the DOJ news release, Kavuru also took advantage of prospective workers. Not only did Kavuru require some of them to pay thousands of dollars to submit the visa applications — a violation of Department of Labor rules — he also “benched” those workers without pay, sometimes for months, as they waited for real jobs with tech firms to materialize, the DOJ said.

News of this latest indictment will likely fuel arguments that the H-1B program is being abused by companies to get cheap foreign labor at the expense of jobs for Americans. In September, an Indian citizen, Pradyumna Kumar Samal, 49, who ran two U.S. staffing firms in Washington State, was charged with engineering what federal authorities are calling a “multi-year visa-fraud scheme” centered on the controversial H-1B visa.

Major technology firms have lobbied aggressively for expansion of the H-1B visa program, arguing that they need access to the world’s top talent to fill highly-technical jobs. But critics point to alleged abuses in which American workers at UC San Francisco and Disney were reportedly forced to train Indian replacement workers.

The indictment unsealed Friday charges Kavuru with 10 counts of visa fraud and 10 counts of mail fraud. His consulting companies are Scopus Consulting Group, ITECH Analyst Corp., Infinity Methods Corp., and Orian Engineering Inc.

If convicted, Kavuru faces up to 10 years in prison and a $250,000 fine.

(Ethan Baron of the Mercury News contributed to this report.)