DENVER - Taxpayers across Colorado and the country are discovering they are now the victims of identity thieves.
According to tax accountants, criminals are using other people's social security numbers to file fake returns.
They are then taking the refund.
The problem is so big that the Internal Revenue Service is adding 3,000 staffers to combat identity thieves.
Dave Ryan discovered he was the victim while preparing his taxes last year. "We were attempting to file electronically and the IRS told us we had already filed," said Ryan.
Someone stole his wife's social security number and fraudulently filed their taxes electronically. The criminal likely got a refund, based on a false claim.
"We had quite a bit of anxiety. We wanted to know who had actually done this, and how much more had they done?" said Ryan.
Ryan is not alone. According to the IRS, investigators reviewed 898 ID-theft cases in 2012. That's triple the amount of cases from 2011.
"In the last 10 or 15 years, I don't know I've ever had a case," said certified public accountant Sarah Knight.
Knight says she's noticed a surge of identity theft cases since the popularity of electronic filing.
"We had half a dozen clients last year," she said.
As far as protection, 7NEWS has learned the IRS is beefing up its screening process. The agency claims to have stopped $20 billion in fake returns last year.
"In me at any rate, (it) raised an awareness of the information that people have out there, how it can be used to potentially hurt you in some way," said Ryan.
Experts say people need to try to protect their social security number. They add the IRS will never contact taxpayers by email or social media.