The Criminal Investigation (CI) Unit of the United Internal Revenue Service (IRS) reported an increase in the number of investigations around digital asset reporting.

In its annual report released on Dec. 4, the IRS investigative arm said it had initiated more than 2,676 cases in which it had identified more than $37 billion related to tax and financial crimes in the 2023 fiscal year. According to the team, it had observed an increased use of digital assets, resulting in a rise of related tax investigations.

“These investigations consist of unreported income resulting from failure to report capital gains from the sale of cryptocurrency, income earned from mining cryptocurrency, or income received in the form of cryptocurrency, such as wages, rental income, and gambling winnings,” said the Criminal Investigation Unit. “CI is also seeing evasion of payment violations, where the taxpayer fails to disclose ownership of cryptocurrency in an attempt to shield holdings.”

Starting in 2019, the IRS began requiring U.S. taxpayers to specifically report on digital asset transactions — a question it has continued to add to tax forms in every subsequent year. In the report, CI chief Jim Lee said that “most people using cryptocurrency do so for legitimate purposes,” but digital assets pose a risk for financing terrorism, ransomware attacks, and other illicit activities.

Since it began increasing efforts to investigate crimes involving cryptocurrency in 2015, the IRS has seized more than $10 billion in digital assets. The government body has also proposed new regulations on brokers’ reporting requirements to reduce instances of tax evasion.