Vanessa Hudgens and Austin Butler are officially under a criminal investigation.

Why?

The investigation stems from their recent Valentine’s Day getaway near the Coconino National Forest.

It seems Vanessa Hudgens shared a photo on social media from their getaway that features her name–as well as Austin Butler’s–carved into a rock. The photo has since been deleted, but not before the police were informed of its existence.

Vanessa Hudgens & Austin Butler are being investigated for carving their names into a rock: https://t.co/mnojDn4oWy pic.twitter.com/yV4ZwITbTf

— JustJared.com (@JustJared) February 16, 2016

TMZ reports there is a federal law prohibiting people from “damaging natural surfaces or property of the United States.”

No charges have yet been filed against Vanessa Hudgens or Austin Butler, but that’s because the investigation is ongoing. If they are charged, both could be facing a misdemeanor, as well as a fine of up to $5,000 and six months in jail.

Some of the pictures Austin Butler and Vanessa Hudgens took on their getaway are still on Instagram.

“#sedonadreams,” this one of Vanessa Hudgens is captioned.

A photo posted by Vanessa Hudgens (@vanessahudgens) on Feb 14, 2016 at 1:11pm PST

Did you know it was a federal crime to carve your name or initials into a rock or tree in the U.S.? It’s likely that lots of people are unaware of the law–including Vanessa Hudgens and Austin Butler.

It will be interesting to learn how long this investigation takes and if the two wind up being charged.