Special report: Inside one of the most powerful drug cartel's in Mexico where they make deadly drug fentanyl
Paste BN' chief correspondent, Stuart Ramsay, followed armed gang members as they picked up shipments, mixed toxic chemicals, ground powders in a smoothie maker and hid batches in secret car compartments ready for smuggling.
The Sinaloa drug cartel, one of the most powerful in Mexico, are makers of the opioid drug fentanyl which has killed thousands of users in the United States.