While Americans face slowing priority mail and other post office cutbacks, our pals over in Munich, Germany are in the midst of an altogether smellier problem — Someone (or many someones) is putting dog doodies in the mailboxes around town.

The disgusting dumpings have been going on for a few months, says Time.com, in Munich as well as surrounding districts. It’s a problem for many reasons — beyond the obvious one that that is not where poo goes — but the waste messes with conveyor belts in post office sorting areas and dirties mail boxes, which gets expensive to clean up. And also, no one wants feces on a postcard from mom.

Police are stumped as to who is doing the dirty deeds and why, but have figured out that at least some of the excrement is human. Double gross!

“Maybe a grudge against the post office, weird humor — we just don’t know,” says police spokeswoman Alexandra Schmeitz as to why anyone would do something so nasty.

If your letter does get the fecal treatment, mail employees try to clean it if possible, and put it in a plastic baggie with a note explaining what’s going on.

The post office is offering 4,000 euros for tips leading to the arrest of the dastardly deed-doers, and we’re sure everyone else is holding their breath that the smelly incidents stop.

The Mystery of the Smelly Letters: Who’s Dumping Dog Poop into Munich’s Mail? [Time]

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