The trafficker Zhi Dong Zhang, known by the alias "Brother Wang," is alleged to have worked closely with Mexico's Sinaloa and Jalisco New Generation drug cartels, designated "foreign terrorist organizations" by Washington.

His arrest was confirmed by the Security Secretariat.

Security sources told AFP it is not yet clear if the suspect will be deported from Cuba back to Mexico or a formal extradition process needs to be undertaken.

Detained in Mexico in October 2024, Zhi Dong Zhang was held in a prison in Mexico City awaiting a hearing for his extradition to the United States, where a warrant has been issued for his arrest on money laundering charges.

He was granted house arrest, from which he escaped in July.

Zhi Dong Zhang is considered "a major international money laundering operator," Mexican Security Secretary Omar Garcia Harfuch said last year.

The trafficker was responsible for "establishing connections with other cartels for the transfer of fentanyl from China to Central America, South America, Europe, and the United States," he added.

Washington under President Donald Trump has been applying pressure on Mexico and China to curb drug trafficking, particularly of fentanyl, the powerful painkiller behind an overdose epidemic in the United States.

Fentanyl is a synthetic opioid that is 50 times more powerful than heroin and much easier and cheaper to produce.

It has largely replaced heroin and prescription opioids such as oxycodone as a cause of overdoses in the United States.

President Claudia Sheinbaum's government has ramped up drug seizures under tariff pressure from Trump, who has threatened further punitive measures unless the problem is solved.

Although Mexico has been the main source of fentanyl sold in the United States, Washington has increasingly focused its attention on China-based suppliers of precursor ingredients.

From Havana, two sources close to the case told AFP the detainee would be extradited to Mexico, but did not specify a date or provide details about the process.

Communist Cuba has not officially commented on the reported arrest.