The United States on Monday imposed sanctions on the two fugitive sons of incarcerated Mexican Sinaloa Cartel leader Joaquin “El Chapo” Guzman and announced a reward offer of up to $10 million each for information leading to the arrest or conviction of the men.

The US Treasury on Monday said it’s sanctioning “Los Chapitos,” the faction of the Mexican Sinaloa Cartel controlled by the sons of jailed cartel leader Joaquín “El Chapo” Guzman that Washington says facilitates illicit fentanyl production and trafficking into the country.

The US government is offering a $10 million reward for information leading to the arrest of El Chapos fugitive sons, Ivan and Alfredo Guzman. Authorities say they rebuilt the Sinaloa Cartel and led fentanyl trafficking into the US.