Buildings in Great Falls, Montana, were evacuated last week when people smelled what they thought to be natural gas. 

People did in fact smell gas and several buildings were evacuated.  Crews on the scene figured out the smell was not coming from a gas leak but instead were coming from cards sent out by utility provider Energy West to help people identify the smell of gas, according to the Great Falls Tribune.

Come to find out the cards had been thrown in the trash and when trash crews hauled them off, the scratch-and-sniff panels were activated and could be smelled all over downtown Great Falls.