A 28-year-old San Jose man was charged Thursday in U.S. District Court in Oakland with distributing fentanyl in the form of counterfeit “M30” pills that resulted in a deadly overdose.

U.S. Attorney Stephanie M. Hinds andFBI Special Agent in Charge Robert K. Tripp said in a press release that the criminal complaint opened in court March 16 and filed on Tuesday accused Ian Edward Parrish, 28, of San Jose, of selling two counterfeit Percocet pills to an individual in a bar in Fremont.

The complaint alleges that the counterfeit pills were laced with fentanyl, and that the individual who bought the pills from Parrish consumed one and shortly thereafter died of an overdose.

The complaint charges Parrish with distribution of fentanyl, which carries a statutory maximum maximum of 20 years in prison, a maximum fine of $250,000 and a maximum of 3 years’ supervised release.

At Thursday’s hearing, Parrish was ordered detained. His next federal court appearance is scheduled for March 21 before federal Magistrate Judge Kandis Westmore.

Hinds said the prosecution is the result of an investigation by the FBI and the Fremont Police Department.

Fentanyl is a Schedule II controlled substance, is a highly potent opiate that can be diluted with cutting agents to create counterfeit pills that purport to mimic the effects of Oxycodone, Percocet, and other drugs, Hinds warned. Very small variations in the amount or quality of fentanyl create huge effects on the potency of the counterfeit pills and can easily cause death, she said.

Fentanyl has now become the leading cause of drug overdose deaths in the United States. Counterfeit, fentanyl-laced pills are usually shaped and colored to resemble pills that are sold legitimately at pharmacies.