Colorado pot businesses are increasingly coming under scrutiny from the Internal Revenue Service due to the industry's focus on cash, according to a report Tuesday from Marijuana Business Daily.

Marijuana businesses such as dispensaries are known to deal predominantly in cash due to continued U.S. banking restrictions that make it difficult for them to have bank accounts with federally chartered financial institutions. And those cannabis businesses with bank accounts sometimes have accounts closed once the bank learns about the marijuana-related activities.



Colorado is one of four states where adult recreational use of marijuana was legalized (Washington state, Oregon and Alaska also legalized it.)



An IRS spokesman told CNBC the agency "is prohibited by law from commenting on specific taxpayers."