An Internal Revenue Service spokeswoman says people should be careful of scams involving undelivered income tax refund checks.

Carrie Resch says the annual announcement of undelivered checks prompts scammers to send e-mails to taxpayers saying they have an undelivered refund. She says it's an effort to get the person to provide their bank account information.

The Postal Service in South Dakota has returned about 220 federal refund checks worth nearly $200,000 because of mailing address errors. The IRS says South Dakota taxpayers can still receive the checks.

Resch says people who think they are missing a refund can go to the IRS Web site and click on "where's my refund." The average refund in South Dakota is about $1,150.