Just got the same message. I remember hearing something about this but nothing on the real US Treasury site about it. Guess the scammers aren't afraid of the federal charge for impersonating a federal officer or agency. Blocked that number!
got a voice mail - regarding enforcement tax executed by department of legal affairs , intending your serious attention. you case number is CF xxxxx . Ignoring this message will be an additional second attempt. 202- 800- 0787 - Washington DC call. lady called.
i purely suspect its a scam. so i did not return this call. i entered this number in do not call list / report scam list.