币界网报道：The U.S. Internal Revenue Service (IRS) has issued warning letters to over 10,000 cryptocurrency investors who may have failed to report taxable transactions, signaling intensified enforcement ahead of new 2026 regulations. The letters, targeting taxpayers with potential unreported crypto income, outline steps to correct filings and warn of penalties for non-compliance. This comes as the IRS implements provisions from the 2021 Infrastructure Investment and Jobs Act requiring stricter crypto transaction reporting starting in 2026. The agency has been expanding its crypto enforcement capabilities, including hiring specialized agents and developing blockchain analysis tools. IRS Commissioner Danny Werfel emphasized that cryptocurrency transactions are taxable events, stating "we want to help taxpayers understand their obligations before more stringent reporting requirements take effect." The letters offer taxpayers an opportunity to voluntarily address discrepancies without triggering full audits, though the IRS notes it may pursue further action if responses are inadequate. Industry analysts suggest this campaign reflects growing regulatory scrutiny as digital asset adoption increases.