One of former President Donald Trump’s GOP rivals was arrested on Tuesday after federal authorities accused him of filling 17 sets of false tax documents to the Internal Revenue Service (IRS).

According to The Hill, John Anthony Castro was indicted last week on 33 counts of aiding the preparation of false tax returns. Prosecutors said Castro defrauded the government by running a virtual tax business that provides customers with tax returns beyond what they were owed.

“Castro would promise a significantly higher refund than taxpayers could receive from other preparers and on many occasions, offered to split the additional refund with taxpayers,” prosecutors said in court documents. “In order to achieve these larger refunds, Castro generated false deductions, that were not based in fact, and which were submitted without the taxpayer’s knowledge.”

Castro, who is currently running for the GOP presidential nominee ticket, was arrested after an undercover law enforcement officer posed as a customer for his tax services. Castro promised the officer that he could get him $6,007 in tax returns. Meanwhile, another tax company had already promised the undercover agent a $373 tax return.

Castro then filled out tax forms on behalf of the undercover officer containing nearly $30,000 in fraudulently claimed deductions.

Castro has, however, denied all accusations while adding that he believes the charges against him were politically motivated. Castro added that he settled the tax return matter with the IRS in 2021, with his firm paying about $700,000 to resolve the discrepancies. He maintains that he will not make a guilty plea.

“I don’t care if they offered me one day probation and a slap on the wrist in exchange for a guilty plea,” he said. “This is going to trial. I am going to convince all 12 jurors that I am 100 percent innocent and that this is political retaliation.”

Castro has filed challenges to Trump’s ballot placement in 27 states, arguing that the former president’s involvement in the January 6 Capitol protest amounts to insurrection and violates provisions of the 14th Amendment.

Castro claims the timing of his prosecution proves his indictment was related to his 14th Amendment challenges against Trump.