SAN FRANCISCO (CBS SF) — A 23-year-old San Francisco man has been sentenced to three years in federal prison for illegally selling fentanyl in the city’s troubled Tenderloin District, according to federal prosecutors.

United States Attorney David L. Anderson said Luis Villarreal had pleaded guilty to possessing fentanyl with intent to distribute charges in May.

According to the plea agreement, Villarreal admitted that on February 25th he was arrested on an outstanding warrant while outside the Bill Graham Civic Auditorium in the Tenderloin neighborhood of San Francisco.

At the time of his arrest, San Francisco Police Department officers found him in possession of 160 individually wrapped baggies of fentanyl, 37 individually wrapped baggies of methamphetamine, 29 individual bindles of heroin, and 25 Zubsolv pills—a controlled substance that generally may not be possessed without a license or prescription.

In the plea agreement, Villarreal admitted that he knowingly possessed and intended to distribute all of the recovered narcotics.