Chinese spies are using the Microsoft-owned social media platform LinkedIn to recruit spies, according to intelligence officials in the United States and Europe, who say that foreign agents are approaching thousands of users on the website.

Chinese spies are the most active with regards to exploiting the Microsoft-owned website, LinkedIn, according to a report by the New York Times. The foreign agents have been contacting thousands of Western citizens, including former government officials.

“We’ve seen China’s intelligence services doing this on a mass scale,” said the Director of the National Counterintelligence and Security Center, William R. Evanina. “Instead of dispatching spies to the U.S. to recruit a single target, it’s more efficient to sit behind a computer in China and send out friend requests to thousands of targets using fake profiles.”

Among the individuals that Chinese spies have apparently attempted to recruit include one former senior foreign policy official in the Obama administration, who reportedly received messages from someone on LinkedIn offering to fly him to China and connect him with “well paid” opportunities.

Another person was a former Danish Foreign Ministry official, who received LinkedIn messages from a supposed recruiter at a Chinese headhunting firm, but when he later met with the recruiter— who was depicted as a woman on the site — three middle-aged men showed up instead, claiming that they could help him gain “great access to the Chinese system.”

A third individual, a former Obama White House official, was reportedly befriended on LinkedIn by someone who claimed to be connected to White House aides and ambassadors, as well as a research fellow at the California Institute of Technology. The report added that no such research fellow exists.

“The Chinese want to build these options with political, academic and business elites,” said the former Danish Foreign Ministry official, Jonas Parello-Plesner. “A lot of this thrives in the gray zone or the spectrum between influence-seeking and interference or classical espionage.”

LinkedIn — a business-oriented social media site mainly used for networking, recruiting, and employment opportunities — is reportedly the only major U.S. social media platform that is not blocked in China, as the company has agreed to censor posts for the communist government.

Given the nature of the platform, former officials are especially vulnerable to these types of recruitment attempts, as they are likely seeking out new employment opportunities, notes Parello-Plesner.

LinkedIn says it has a team at the company that works proactively with government agencies — among other sources — to find and remove fake accounts.

“We enforce our policies, which are very clear: The creation of a fake account or fraudulent activity with an intent to mislead or lie to our members is a violation of our terms of service,” said LinkedIn spokesperson Nicole Leverich.

Last week, Facebook and Twitter announced that the platforms were removing “inauthentic” accounts discovered to be operated from within the Chinese government.

The social media platforms say that the fake “state-backed” accounts that have been “deliberately and specifically attempting to sow political discord in Hong Kong, including undermining the legitimacy and political positions of the protest movement on the ground.”

You can follow Alana Mastrangelo on Twitter at @ARmastrangelo, on Parler at @alana, and on Instagram.