I did and called back the number. something about owing the IRS $6,000, after I questioned the guy what was my SS number to make sure it was me they were looking for. He said my neighborhood police department will be coming to my house to arrest me and hung up.
Bull s*** "IRS about to sue me", please call, Posing as an IRS Enforcement is a felony, they should be drawn and quartered. Computer generated crud. If the IRS has ANY offical business with you they conduct it by mail