GREEN BAY, Wis. – The scares have gotten real at a popular haunted house attraction in Wisconsin.

Workers at Terror on the Fox near Green Bay made an unexpected discovery when they were pulling caskets out of storage, WFRV reported.

Workers found two human skeletons inside the two vintage coffins that date back to the early 1900s, if not earlier.

Workers said the caskets were donated five years ago by a funeral home, the Green Bay Press-Gazette reported.

The person who donated them told the owners of Terror on the Fox that one of the caskets held remains when the coffins were put into storage.

They were uncovered when a designer was looking for more bones to fill the catacomb section of the haunted house after it was remodeled.

Mike Krausert, senior project manager for Terror on the Fox, said they are medical skeletons that date to the late 19th century, the Press-Gazette reported.

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The remains have been included in the catacomb display, but they are behind wires that prevent visitors from touching them.

“Legally, if you can prove where they came from, you’re OK to have them and use them. We made sure everything was right in line with what we were able to do or not do,” Krausert said.

The attraction’s owners are not sure what they’re going to do with the skeletons after the season wraps on Nov. 5. They may keep or donate the skeletons, the Press-Gazette reported.

The owners plan to refinish the vintage coffins.

Things got real at a Wisconsin haunted house after workers made this terrifying discovery Twitter Screenshot/Terror on the Fox