Mexico’s notorious Sinaloa cartel, once ruled by now-jailed drug kingpin Joaquin “El Chapo” Guzman, has barred the production of fentanyl — under penalty of death.

The about-face by the narco crew — the main trafficker of the deadly synthetic opioid flooding the US — comes as El Chapo’s kids bow to a mounting law enforcement crackdown on the drug trade, the Wall Street Journal reported Monday.

The order came from the “Chapitos” — the name for Guzman’s sons, who took over the operation.

“In Sinaloa, the sale, manufacture, transport or any kind of business involving the substance known as fentanyl, including the sale of chemical products for its elaboration, is permanently banned,” said one of several banners hung on billboards and overpasses in Culiacan.

“You have been warned,” the message read. “Sincerely yours, the Chapitos.”

US law enforcement officials are skeptical about the decree, and said the ban is expected to do little to curb the fentanyl trade — and could lead to an increase in heroin and cocaine trafficking. “In the aggregate, it won’t mean anything,” one law enforcement official told the Journal. “They think if they do this, they won’t take as much heat.”

Nonetheless, the cartel sent a gruesome message in June, when three bodies covered in blue fentanyl pills were found on the outskirts of Culiacan — a grim reminder that the Chapitos mean business.

Over the past 10 days, about a dozen more people have been kidnapped in Sinaloa, most of them believed to be linked to the fentanyl trade in the area.

“We believe these kidnappings and disappearances are linked to the ban on fentanyl because their relatives have been presented formal complaints to authorities,” said Michael Angel Murillo, a human rights activist with the Sinaloa Civic Front, a grassroots group.

“These people are very scared.”

    El Chapo ran the drug empire for decades before he was extradited 

to the US in 2017.

He was found guilty of narco-trafficking two years later and ordered jailed at a supermax federal prison in Colorado.
US drug enforcement and Mexican officials turned their attention to the former kingpin’s sons, and in January captured Ovidio Guzman, the Chapitos’ top leader, after a deadly gun battle that left at least 29 people dead — including a Mexican army colonel.

Ovidio Guzman was extradited to the US last month, while four Guzman brothers and about two dozen Sinaloa associates were indicted by US federal prosecutors in April.