The United States’ top spy catcher said Chinese espionage 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, the US counter-intelligence chief, told Reuters in an interview that intelligence and law enforcement officials have told LinkedIn, owned by Microsoft Corp., about China’s “super aggressive” efforts on the site.

He said the Chinese campaign includes contacting thousands of LinkedIn members at a time, but he declined to say the details including how many fake accounts US intelligence had discovered, the number of Americans they have contacted and how much success China has had in the recruitment drive.

German and British authorities have previously warned their citizens that Beijing is using LinkedIn to try to recruit them as spies. But this is the first time a US official has publicly discussed the challenge in the United States and indicated it is a bigger problem than previously known.Evanina said LinkedIn should look at copying the response of Twitter, Google and Facebook, which have all purged fake accounts allegedly linked to Iranian and Russian intelligence agencies.

“I recently saw that Twitter is canceling, I don’t know, millions of fake accounts, and our request would be maybe LinkedIn could go ahead and be part of that,” said Evanina, who heads the US National Counter-Intelligence and Security Center.

Evanina felt that LinkedIn should follow the paths of other social media companies to check the fake activities.It is highly unusual for a senior US intelligence official to single out an American-owned company by name and publicly recommend it take action. LinkedIn boasts 562 million users in more than 200 counties and territories, including 149 million US members.

LinkedIn’s head of trust and safety, Paul Rockwell, confirmed the company had been talking to US law enforcement agencies about Chinese espionage efforts. Earlier this month, LinkedIn said it had taken down “less than 40” fake accounts whose users were attempting to contact LinkedIn members associated with unidentified political organizations

Rockwell declined to provide numbers of fake accounts associated with Chinese intelligence agencies. He said the company takes “very prompt action to restrict accounts and mitigate and stop any essential damage that can happen” but gave no details.