"Suspicious Bicycle"

My wife just got one of those all-points office emails stating in part, "The 1700 Block of F Street is closed due to a suspicious bicycle in the vicinity of 17^th and F Streets." Suspicious bicycle? What do you want to bet that somebody locked up a bike with a "This Bike is a Pipe Bomb" sticker?

[edit -- turns out, this exact scenario reportedly occurred in Ohio. I plagiarized reality.]