FAIRFIELD — His passenger wasn’t wearing a seat belt and that led to Joseph Rivera, 32, arrested on drug charges.

An officer saw a car driving on the Post Road Tuesday afternoon. The passenger wasn’t using his seat belt, and large clouds of smoke that smelled of marijuana emanated from the car’s open windows. The officer stopped the car, and as he approached it, the pot odor grew stronger, according to the police report.

Rivera, of Prospect Street in Ansonia, told police there might be some marijuana roaches in the car. The officer located the roaches and three glass jars with marijuana packaged for sale in a backpack on the back seat.

He was charged with possession of a controlled substance and possession with intent to sell. Rivera was released on a promise to appear in state Superior Court in Bridgeport March 6. His passenger was given a verbal warning for not wearing a seat belt.