I just realized much of this article is behind the WSJ.com paywall. Here are some of the key points:

- The Federal Bureau of Investigation has opened a probe to determine whether a computer data breach led to the filing of false tax returns through TurboTax software, according to a person familiar with the case

- FBI investigators are still working to determine exactly how personal information was obtained to file bogus returns in about 19 states and whether that information may have been stolen from TurboTax or somewhere else, the person said

- Some state tax officials and security specialists said they have seen cases of fraudulent state and federal tax returns that apparently include data obtained from 2013 tax returns. Some state officials have said problems seem to be concentrated in returns submitted through TurboTax

- Officials at competitors H&R Block Inc. and TaxAct, a unit of Blucora Inc., on Tuesday reiterated statements that they haven’t seen unusual levels of fraud activity recently.

- “We don’t know where the information is being taken from, as no one wants to admit that they have had a breach. But this is absolutely the biggest year ever for the theft of information from prior tax returns being used to file fraudulent returns, and this problem is getting worse,” Mr. Abagnale said. As a young man, Mr. Abagnale was convicted of fraud-related crimes and served time in French, Swedish, and U.S. prisons. His early life was portrayed in the film “Catch Me If You Can.”

- Dave Harmon, a business owner in St. Louis, is one TurboTax user who found a fraudulent federal return had been filed in his name and with data that seemed to come from his 2013 return. He said he received an email on Jan. 22 from TurboTax congratulating him on finishing his federal return, although he hadn’t done so. When he printed a copy of the fraudulent return from his TurboTax account, he found that the numbers on Schedule A for itemized deductions were the same as on his 2013 return. Someone “had to have access to everything in my return” from last year, he said. He said his password was “relatively complex,” with one capital letter, six other letters and four numbers.

- Craig Hollowell, a salesman for TranSouth Logistics in Douglasville, Ga., discovered he was a victim on Saturday morning, when he called TurboTax with a question about downloading tax information from a brokerage account and was told that someone had filed his federal return two days before.

- The IRS has estimated that it paid $5.2 billion in fraudulent identity-theft-related refunds in the 2013 tax season, while blocking attempts to collect another $24.2 billion. “We closely monitor incoming tax returns, watching for fraud indicators and adjusting our systems as necessary,” the IRS spokeswoman said. “Preventing and detecting identity theft and refund fraud remains a top priority for the IRS.”

- South Carolina has isolated 96,000 TurboTax returns to check them for fraud, according to Rick Reames, director of the Department of Revenue. He said the number of returns filed through TurboTax is about 15,000 higher than at a similar time last year. In 2012, the South Carolina department had a data breach that exposed information from 3.9 million state tax returns.

edit: formatting