Thousands of Americans have been getting calls about alleged unpaid taxes, reports Yahoo Finance.

Turns out, the calls are part of a nationwide scam—one of the largest tax-fraud scams ever recorded, adds the outlet.

The Treasury Inspector General for Tax Administration has received more than 20,000 complaints about callers who claim to be from the IRS. Read more.

This report comes shortly after a data breach scare at the IRS, which involved an employee taking a flash drive home that contained the data of agency employees and contractors.

For more on taxes, read:

Canadians confused when filing taxes

Tax planning for business

Tax credits for seniors

Tax tips for new homeowners