What are the warning signs of income tax related identity theft?

Warning signs may include:

1. Receiving an unexpected notice from the Michigan Department of Treasury, Internal Revenue Service or another state income tax agency regarding your account.
2. More than one tax return was filed using your Social Security number (SSN). You may be unaware you are a victim until you try to file your return and learn one already has been filed using your SSN.
3. Receiving a notice or billing for a year in which you did not file a tax return or have a filing requirement.