The United States' top spy catcher says Chinese spy agencies are using fake LinkedIn accounts to try to recruit Americans with access to government and commercial secrets, and the company should shut them down.

William Evanina, who heads the U.S. National Counter-Intelligence and Security Center, said in an interview that intelligence and law enforcement officials have told LinkedIn, owned by Microsoft Corp., about China's "superaggressive" efforts on the site.

He said the Chinese campaign includes contacting thousands of LinkedIn members at a time. He declined to say how many fake accounts U.S. intelligence has discovered, how many Americans may have been contacted and how much success China has had in the recruitment drive.