HiddenCash is a Twitter account that posts clues to envelopes of cash around the world. Recently, a tweet pointed searchers to a park in Whittier, CA.
Unfortunately, in the searchers' haste to find the money, many parts of the park were badly damaged.
The account describes itself as "An anonymous social experiment for good" in its Twitter bio.
Similar hunts have taken place around the world, including London, where it went off without a hitch.
But the hunt in William Penn Park resulted in significant damage to the area, a place where wildlife is known to live.
The organiser of the hunt has since apologised online, saying, "Doing a drop at a small park in Whittier after dark was probably not the smartest idea."
"Other events all went very well, including those in 'poor' parts of town, like east LA."
"Going forward, we will learn from this. As the crowds are big, event locations need to be selected even more carefully."
He's also agreed to reimburse the exact amount of damage the hunt caused.