Jose Rosado, 34, of Florence, was arrested on March 24, after police found the synthetic opioid during the stop along Route 91 in Holyoke, Massachusetts State Police said on Friday, March 31.
Officers seized 150 half-packages of fentanyl.
Rosado is charged with trafficking an amount of heroin/fentanyl between 100-200 grams.
For context, the DEA says a fatal dose of fentanyl can be as little as two milligrams.
Rosado's arrest was a joint effort with state police narcotics officers, Springfield police, agents from the DEA's Springfield Office, the Northwestern District Anti-Crime Task Force, and the State Police Detective Unit for Hampden County.
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