SAN ANTONIO -

Fake tax returns is the fastest growing identity theft scheme going, according to the Federal Trade Commission.

And, the IRS says the combating the growing threat is a top priority.

"Identity theft is a huge deal for the IRS right now," said IRS special agent Michael Lemoine.

He said the San Antonio office for criminal investigations is seeing its workload escalate.

Last month, 69-year-old  Daniel Henry Lopez was sentenced to 51 months in federal prison for stealing the names, Social Security numbers and birth dates of people he met while working at Veterans Affairs rehabilitation facilities and filing fake tax returns. The refunds, totaling approximately $78,000 was electronically deposited into fraudulent bank accounts also set up using the stolen identities.

"He was a veteran himself," Lemoine said. "He was preying on his own kind, which is really despicable."

Approximately 1 million cases of tax identity theft were filed last year across the nation. Thieves simply type in stolen personal data including Social Security numbers and invent incomes. The victims are unaware.

"They think they're fine, and they go to file a tax return with the IRS and boom, it gets rejected because someone already stole their identity and filed a tax return for them," Lemoine said.

To protect yourself, experts advise you use use a secure Post Office mailbox instead of home mailbox is filing by mail. Also, when filing electronically, make sure the computer and network are secure.

Protecting Social Security numbers is key. And,  if you file early, you win the race against the ID crook.

The IRS has these tips: