Rihanna's Diamonds World Tour has endured a few hiccups since it began two weeks ago in Buffalo, N.Y. Along with a few show cancellations, RiRi has suffered yet another roadblock, this time at the Canadian border.

According to TMZ, a fleet of 10 buses were stopped at the Ambassador Bridge, which separates the state of Michigan and Canada, for a bus-to-bus search. When authorities brought their drug-sniffing dogs, they discovered that one passenger was in possession of a small amount of weed.

Oddly enough, Rihanna was not on any of the buses -- so we have to assume she flies to her concert destinations. In any case, the passenger was cited with a civil penalty and was sent on his way.

Now we all know that the 'Pour It Up' singer likes to engage in smoking activities related to the sticky icky. Lucky for her she wasn't caught up in the incident with the buses.

Hopefully, Rihanna is informed about this episode and plans to stay sober for the rest of the trek. For her sake and for the betterment of her voice, notwithstanding.

Watch out for the po-po, RiRi!

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