The FBI said it has seen an increasing number of cases in which fraudsters use LinkedIn to find their victims. Sean Ragan, the FBI’s special agent in charge of the San Francisco and Sacramento, California, field offices, sat down for an exclusive interview with CNBC to detail how the scams work.

Ragan explained that many instances of fraud involve cryptocurrency. He said that the scammers will create fake profiles and use them to send private messages to their potential victims. In some cases, they will spend several weeks or months gaining the trust of their victims before attempting to scam them.

The scam usually starts with an offer to make money by investing in cryptocurrency. To give the scam the appearance of being legitimate, the fraudsters instruct their victims to invest using well-known platforms.

Then, after a few months, the scammers convince their victim to move the money to another site, which they control.

Once the money is moved, the scammers then withdraw everything.

LinkedIn issued a statement to CNBC saying that they actively work to prevent fraud and spam from spreading on their platform.

“Our teams use technology like artificial intelligence paired with teams of experts to stop the vast majority of content that violates these policies before it ever goes live – 96% of detected fake accounts and 99.1% of spam and scams are caught and removed by our automated defenses,” the company explained in a blog post.