Vanessa Hudgens and Austin Butler's Valentine's Day vacation sparked a criminal investigation accusing the couple of defacing a rock formation in Sedona, Ariz., according to TMZ.

The "Grease: Live!" star and the "Arrow" actor allegedly carved their names inside a heart onto a rock formation. Little did they know, there's a federal law that forbids anyone from "damaging natural surfaces or property of the United States."

It all started when Hudgens posted several photos of her vacation on Instagram, including a picture showing the couple's names in a heart. The post has since been deleted, but not before it caught the eye of forest officials, according to E!.

"Officials at the Coconino National Forest became aware of the incident [Monday] when the media alerted them of the situation," said the forest's public affairs officer, according to Entertainment Tonight. "There is no deadline for this investigation - it takes as long as it takes. The maximum punishment for this is $5k and/or 6 months behind bars."