Threatening.  Male caller left message on our home machine and told us we had to call him back to avoid magistrate or grand jury investigation because of a criminal offense.  If we do not call him we could face jail time.  He left this number (which matched the caller ID) but did not identify himself or who he [purportedly] worked for.

I received the same call today. Foreign accent and said I committed a federal offense. Yeah....sure

Just received same exact message as previous poster. Totally bogus.

We have received 2 calls in the last 2 weeks from men with noticeable foreign accents threatening action by the IRS (a warrant for our arrest, the need to appear before a federal magistrate, etc.) unless we called them back at this number and "cooperated."  We reported the calls to our local police department and was told that they'd received "thousands" of complaints. The police also told us that the calls couldn't be stopped or traced because they were coming from a telephone number outside the U.S. These crooks apparently also have an app that generates a U.S. phone number and causes the local number to appear on a U.S. caller i.d.  Don't call them back or do anything else that might encourage them!

LOL, I hit the auto redial and the recording says no such number.

Probably foreign cyber terrorists trying to incite panic in the land of the great Satan...

I mean who says magistrate?!?!?

Per http://en.wikipedia.org/wiki/Magistrate#United_States

United States
Magistrates are somewhat less common in the United States than in Europe

People's Republic of China
Magistrate, or chief magistrate, is also a common translation of the Chinese xianzhang

Ha ha, busted you stupid Mongolian hackers!

:P