Passing along this warning sent to the post-doc communty about a type of scam that has continued to find victims, including recently among the Brown postdoc community.
There are multiple variations, but they usually involve a caller presenting some scenario where the victim feels pressured to transfer their money to another bank account or bitcoin account. The caller may have some of the victim's personal information (perhaps even part of the victim's Social Security #) and can be quite convincing. The scammer threatens to call the police if money isn't handed over, or threatens that US marshals will confiscate the victim's funds if they don't transfer the money to another account. In one scenario the scammer claims to represent the IRS and demands payment for a non-existent federal tax.
Note that the IRS will never demand immediate payment over the phone. You can read more about the scam on the IRS website.