Law enforcement officials found a small amount of marijuana on one of Rihanna's tour buses when they were stopped at the border between Michigan and Canada, according to a TMZ report.

Some 10 buses were stopped at the Ambassador Bridge, which separates Canada from Detroit. According to TMZ, law enforcement officials found weed and initiated a bus-to-bus search. 

RIhanna wasn't on any of the buses, TMZ reports. 

[via TMZ]

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