Authorities stoped Rihanna’s tour bus this week after smelling marijuana. 

Ten buses were stopped at the border between Michigan and Canada where inspectors uncovered the herbal drug on one passenger.  Rihanna was not on any of the buses. 

Inspectors brought in drug-sniffing dogs when inspectors caught a whiff of marijuana on one of the buses.  The hounds apparently sniffed out the one passenger who was cited with a civil penalty. 

Rihanna just wrapped up a two-night stand in Toronto on Monday and Tuesday.  She is scheduled to perform in Chicago on Friday.