Michelle Quinn filed her tax return in January and got the good news that she was due a refund of about $8,000.

But days after the refund was supposed to arrive, the 33-year-old mother of three still didn’t see the cash in her bank account. When Quinn logged onto TurboTax, she learned that her refund had in fact been deposited — into someone else’s bank.

Quinn is the victim of a form of tax-related identity theft that fraud experts say is uncommon. Most people find out they’re victims after their tax returns are rejected because someone else has already filed in their name. But Quinn’s refund was stolen after she filed her return and the IRS accepted it. Before her refund was deposited, someone changed the bank account information.

Between 24 and 40 taxpayers had their refunds stolen this way, according to Intuit, the maker of TurboTax, and Green Dot Corporation, a bank that works with tax-preparation firms to issue refunds. Like Quinn, all of the customers had elected to have their filing fees pulled from their refunds through what’s called a refund transfer. About two dozen of those customers used TurboTax.

Refunds are typically deposited with Tax Products Group, which is owned by Green Dot, and then passed along to the taxpayer after TurboTax’s fees are withdrawn. Fraudsters who had obtained the taxpayers’ personal information were able to funnel the refunds into another bank account, said Julie Miller, a spokeswoman for Intuit.

These cases highlight the different ways that people can cheat the system after accessing a person’s online tax account or obtaining sensitive tax information. The IRS and state tax officials, which are ultimately responsible for determining if a tax return is fraudulent, are struggling to keep up with the rising sophistication of online tax criminals.

So are online tax preparation firms. A spike in suspicious state filings through TurboTax earlier this season caused the company to temporarily halt the transmission of state returns and gained the attention of Congress, the FBI and the Justice Department, which launched probes into tax fraud. State tax authorities say that the fraud isn’t unique to any one tax preparation Web site.

Miller said that some of the additional security measures Intuit rolled out in early February should prevent other criminals from making a similar move. People who sign onto their TurboTax accounts or who want to access their refunds through Tax Products Group now have to confirm their identities by answering questions about their credit histories.

Miller said Intuit offered to front tax refunds for customers affected by the Tax Products Group incident while the IRS and law enforcement officials investigated the case. About two-thirds of the people should have their refunds by now, she said. “Because of the unusual circumstances we just want to make sure that those customers are made whole,” Miller said.

Quinn says that she declined the offer and decided to work directly with the IRS to recover the money. “I really didn’t feel comfortable with it,” said Quinn, who received a letter from Intuit last week letting her know that someone may have accessed her TurboTax account.

On the Web site for Tax Products Group, customers can create an account by including a Social Security number, refund amount and filing status.

While Quinn says she knew that her refund would be processed through Tax Products Group, she wasn’t aware that she could create an account there.

Tax Products Group said it rolled out new security measures after noticing suspicious activity earlier this year. “TPG works hard to protect innocent tax payers from being victimized by tax fraud,” the company said in a statement.

An IRS official said the agency does not comment on individual taxpayers or tax returns. It has been looking for new ways to combat tax fraud, and last week IRS Commissioner John Koskinen met with Intuit, H&R Block and state tax authorities to call for fixes that can be rolled out by next tax season.

Possible solutions include requiring companies to report W-2 forms and other income information to the IRS earlier or delaying refunds to give tax agencies more time to catch fraud. Miller said Intuit is considering more steps to spot suspicious returns and that it may start to flag customers who change their bank account information, because that may be a sign that the account was taken over by a fraudster.

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