Fentanyl was developed as a legal, and effective, pain killer. Now, fuelled by insatiable US demand, it’s illicitly produced in makeshift laboratories in Mexico by organised crime groups.

In the first of a two-part series, Assignment travels to the Mexican Pacific port of Manzanillo. This is one of the main entry points for the chemical ingredients required to make fentanyl. It’s a town where Mexico’s powerful cartels have fought for control, and where the mayor lives under armed guard after a failed assassination attempt.

Although the primary destination of Mexican-made fentanyl is the US, Mexico too has a rising number of addicts – especially in Tijuana on the Mexico / US border.

Presenter / producer: Linda Pressly

Producer: Tim Mansel

Producer in Mexico: Ulises Escamilla

[Photo: The Navy is in charge of security at Mexico’s seaports in a bid to stop the chemicals used to make fentanyl coming in from Asia. Credit: Tim Mansel]