A key offshoot of the notorious Sinaloa cartel led by the sons of former Mexican drug lord Joaquin “El Chapo” Guzman has banned the production and sale of fentanyl in Sinaloa state, surprising analysts worldwide.

The ban “order” was made known by banners – or narcomantas, as they are known – posted on state roads, signed by the “Chapitos”, Guzmán’s sons who took over running his criminal empire after their father he was extradited in 2017 to the US, where he is now serving a life sentence.

“The sale, production, transportation or any business activity involving the substance known as fentanyl is strictly prohibited in Sinaloa,” the banners read.

In fact, those who do not comply with the leaders’ instructions will be murdered.

It is not clear who hung the banners on bridges and uneven junctions. But they came as US authorities step up pressure on those in Mexico to crack down on gangs involved in the production of fentanyl.

However, analysts remain skeptical as to whether the gang actually intends to abandon this highly lucrative business.

THE US government this year accused the Chapitos (the “little Chapos”) of being the main suppliers of fentanyl to the US market. Last month Ovidio Guzmán, the youngest of the four “Tsapitos”, was extradited to the US.