A snorkeler in Arizona was spooked by two skeletons lounging in lawn chairs at the bottom of the Colorado River.

The man found the skeletons 40 feet underwater and reported them to authorities – only to learn they were fake.

‘Devil Baby’ Terrifies New Yorkers in Prank Video

The La Paz County Sheriff’s Office called the bizarre scene an underwater tea party.

The Associated Press reported:

The skeletons are wearing sunglasses, and one is holding a sign that includes the words "Bernie" and "dream in the river," although the entire sign is not legible. The sign also has the date of Aug. 16, 2014, which is possibly when the skeletons were placed there. […] The sign could be a reference to the movie "Weekend at Bernie's," in which the two main characters lug around their dead boss for days, losing and recovering his body several times, Bagby said. At one point in the film, Bernie's corpse falls off a boat and into water.

Grandma-to-Be's Priceless Reaction to 'Bun in the Oven' Prank

Bill Hemmer asked Lt. Curt Bagby on “America’s Newsroom” if the sheriff’s office has any clues that could lead to the pranksters.

“No sir, just the skeleton and one scared snorkeler,” Bagby said.

Bagby said that the snorkeler seemed genuinely concerned when he found the skeletons – and then genuinely embarrassed when he realized they weren’t real.

Watch Bagby's interview above, and see footage from the underwater tea party below.