The federal income tax deadline of April 15 is just over a week away. Since early in the year and leading up to Tax Day, scammers have been preying on unsuspecting people by calling, pretending to be from the Internal Revenue Service and threatening legal action or arrest unless immediate payments are made.

It’s a terrible crime, with innocent victims feeling pressured by threats from people claiming to be IRS agents. The scammers can be convincing, and just hearing “I’m from the IRS” can make anyone nervous.

The good news is that this scam can be stopped with some education, and by extension, warning relatives or friends who might be targeted.

A recent report by National Public Radio on the widespread scam put it well, saying “If a caller says, ‘I am with the IRS,’ he’s not.”

It’s really that simple. The IRS communicates with taxpayers through regular mail.

Remember, the IRS does not call. The IRS does not e-mail. So, any phone call or e-mail claiming to be from the IRS is a scam.

IRS Commissioner John Koskinen spoke recently at the National Press Club in Washington, D.C., on the topic of scammers pretending to be from the IRS. Koskinen noted that con artists might know the last four digits of person’s Social Security number, but warns that crooks get that easily from stolen computer data. He also admitted that the con artist-crooks can sound convincing and their threats can be scary.

Nationwide, IRS phone scams are believed to have fooled about 5,000 people and gotten away with tens of millions of dollars. More than 250,000 people nationwide have complained of receiving these kinds of calls. Assuming that not everyone receiving one of these calls reports it to authorities, the actual number is probably much higher.

Of the scam, Koskinen says simply, “Don’t fall for it.”

Other experts say never to send money or provide the caller with a credit card or bank routing and account numbers. Scammers often suggest to callers that a prepaid debit card is the best way to quickly settle up with the IRS. Again, the experts say, don’t do it.

Koskinen and others also suggest that people who are aware of this scam call their parents or grandparents to remind them of the callers’ techniques. The elderly and immigrants are the most vulnerable to the threats in these tax scams.

Knowing that the IRS communicates only by mail should give people the confidence to resist the scammers, despite the threats of lawsuits or jail. If someone is still unsure if it’s really the IRS, they can request that the tax notice be mailed to them. Or they can ask for a phone number and offer to call back after talking with their accountant or a friend. That kind of response will probably cause the scammer to hang up — and move on to calling another potential victim.

Beyond the statement that it never calls or e-mails taxpayers, the IRS offers some scam warning signs, including, demands for immediate payment or if the caller dictats the method of payment, such as prepaid debit card. The IRS also says threats of lawsuits or arrest are other red flags that the call is a scam.

Still, the best tipoff is the call itself. If a caller, or an email, claims to be from the IRS, you know it’s a scam. Don’t fall for it.