MIAMI -

The former mayor of Hialeah and his wife pleaded not guilty to federal tax evasion charges.

Julio and Raiza Villacis Robaina were arraigned in Miami Friday on charges of conspiring to defraud the U.S., filing a false tax return, and making false statements to investigators. Each charge carries a potential five-year prison sentence.

"We are extremely proud and humbled by the amount of support that we have received," said Julio Robaina. "From phone calls, emails, texts, family, friends -- we are, my wife and I, are extremely humbled by it."

The Robainas are accused of receiving undisclosed cash payments as interest on more than $1 million in personal loans they made to old friends and associates, including convicted Ponzi schemer Luis Felipe Perez.

IRS agents examined Robaina's bank and other financial records for any deposits that seemed out of the ordinary for evidence that showed he evaded paying his full share of taxes. If a person receives any kind of interest payment on a loan, federal law requires that income to be reported to the IRS for possible taxation.

"Today is the first step of a process," said Julio Robaina. "We believe in the justice system. We know that when the facts are told in our day in court, that we will be vindicated, our names will be cleared, and we will continue to help in this community."

Despite the charges, their supporters were unfazed.

"We believe in him. We believe in her," said Reina Guanthe.

"It's a symbol and a reality to support of his impeccable, municipal administration," said former Hialeah councilman Jose Caragol.

READ: Indictment filed against the Robainas |

Julio Robaina was Hialeah's mayor from 2005 to 2011 and ran unsuccessfully for mayor of Miami-Dade County.