Mysterious monolith appears in Wauwatosa park then disappears

WAUWATOSA, Wis. (CBS 58) -- What started in Utah has seemingly spread around the world. Monoliths are appearing in random locations and no one knows why. Many of them disappear just as mysteriously. Now, we have one right here in Wauwatosa. 

Pictures taken by CBS 58 photographer on Sunday, Jan. 3, show a monolith at County Grounds Park. 

CBS 58 went back Monday, Jan. 4, for another look and found it was already gone. 

What could these mysterious monoliths appearing mean?

We reached out to the Milwaukee County Parks for any information they may have.