The US Treasury announced sanctions Wednesday against 15 Mexican companies and six Mexican people it says are linked to a drug cartel.
The department named the cartel as Los Cuinis and said it is one of Mexico's most powerful and violent drug trafficking organizations.
Under the sanctions, assets that the companies and people may have under US jurisdiction are frozen. Americans are generally prohibited from doing business with them, the Treasury said.
"Today's designation marks the first step in dismantling its significant business network," said John Smith, acting director of the Treasury's Office of Foreign Assets Control.
Violations of the sanctions can be punished with multimillion-dollar fines and prison terms of up to 30 years.
The Los Cuinis cartel is an offshoot from another cartel that was active in the 1990s.
In April, the Treasury slapped sanctions on the cartel itself and its leader Abigael Gonzalez and against an allied cartel, Jalisco Nueva Generacion.
The Treasury Department says that since 2000 it has identified 1,700 companies and people linked to drug trafficking.