Emily Sopel, 34, was charged with having heroin and other drug contraband after a traffic stop on the 300 block of North Washington Street.
Police said Sopel was a passenger in the vehicle of a U-Haul truck being driven by Heather Kuhrt, 33, of Butler, who was wanted on a bench warrant. Kuhrt was arrested on the warrant that was issued after she failed to appear for a hearing in a misdemeanor drug case.
When Sopel got out of the truck, a city police officer noticed that she had been sitting on a stamp bag of heroin.
In the passenger side door pocket police said they found at least three more empty stamp bags.
Additionally, she is accused of having a hypodermic needle.
Sopel is charged with possession of a controlled substance and drug paraphernalia.