In an attempt to catch people off guard, crooks are posing as IRS agents and hoping callers will hand over enough personal information—Social Security number, date of birth, and so on--so the crook can commit identity theft.

It's an effective scam, especially for people who fear an audit. And older people are particularly susceptible because they're more trusting.

What should you do if you get a call from someone who claims to be from the IRS?

Be suspicious from the get-go. Remember that the IRS almost never calls taxpayers and never asks for credit card numbers, financial account numbers, or personal identification numbers over the phone. Ask for the agent's name. Then hang up and call the IRS at 800-829-1040 to confirm that the caller is an IRS employee. Don't use any other phone number that the caller gives you--it's probably a fake. Report the call to the Treasury inspector general's fraud-referral hot line at 800-366-4484.