An IRS agent revealed that Paul Manafort had at least $16 million in unreported taxable business income over four years while testifying during the former Trump campaign chairman’s trial for tax and bank fraud on Wednesday.

IRS agent Michael Welch said in federal court in Alexandria, Virginia, that Manafort received $15.5 million from Ukraine which he then used to pay for clothes, homes and landscaping between 2010 and 2014.

Manafort also falsely classified another $1.5 million in income as a loan, Welch testified — while adding that Manafort never indicated he had foreign bank accounts on his tax returns.

“They failed to check the box that Mr. Manafort had a foreign bank account,” Welch said, later adding. “He should have marked the box, ‘Yes.’”

In addition to the unreported income, Welch said that Manafort listed dubious business expenses such as 132,000 euros to a yacht company, $49,000 for an Italian villa rental, $45,000 for cosmetic dentistry and $19,800 for a riding academy, according to The Washington Post.

Welch, a 34-year IRS veteran who worked on more than 500 criminal investigations, is an expert witness in the trial.

Earlier on Wednesday, Manafort’s protégé Rick Gates wrapped up his three days of testimony after admitting he lied, committed crimes with Manafort, stole money from his boss and cheated on his wife.

Lawyers for Manafort used the opportunity to scrutinize Gates’ personal foibles, asking if he had a “secret life” from 2010 to 2014.

Defense lawyer Kevin Downing saw an opening to undermine his testimony by painting him as a liar and a philanderer.

Downing asked Gates if he had told the special counsel’s office that “you actually engaged in four extramarital affairs?”

Gates, a married father of four, replied, “Mr. Downing, I’d say I made many mistakes, over many years.”

Gates testified on Tuesday that he once had an extramarital affair that involved maintaining a London apartment.

He testified under terms of a deal with Justice Department Special Counsel Robert Mueller, who’s investigating suspected collusion between Russia and Trump’s campaign during the 2016 presidential election. He faces up to six years in prison under the deal.

Also on Wednesday, an FBI forensic accountant, Morgan Magionos, told jurors bank records from Cyprus, St. Vincent and the Grenadines and the United Kingdom revealed the accounts were connected to Manafort and his associates.

She said Manafort’s passport was used to open many of them in US dollars, euros and British pounds.

Using charts, emails and financial and tax records, Magionos told jurors how she traced millions of dollars back to his hidden foreign bank accounts. In one case, she alleged that foreign accounts were used by Manafort to pay for more than $3.5 million in home improvements.

Konstantin Kilimnik, a man prosecutors say has ties to Russian intelligence, was also among the beneficial owners of some of the companies. Kilimnik is charged along with Manafort with witness tampering in a separate case. Gates was also listed as an owner of several of the accounts.

With Associated Press