NEW YORK, NY.- Three tourists from Germany who were accused of firing paintballs at signs, bathrooms and dumpsters in Joshua Tree National Park in Southern California were cited for defacing property, according to park officials.

The damage was discovered Sunday on a patrol of a campground after a park ranger found “fresh yellow paintball splatter on structures and signs,” the National Park Service said in a release Thursday.

Rangers who investigated the area spotted a slingshot in plain view in a vehicle at the campground, the release said. They questioned the tourists, who admitted to firing paintballs with slingshots and a compressed paintball gun the night before. At least 11 signs in the park had been shot with yellow paintballs, the release said, and rangers searching their vehicle recovered paintball equipment as evidence.

The park service did not name the tourists, but said they were visiting from Germany. They were given a federal notice violation for “vandalizing, defacing or destroying property,” the park service said, adding that paintball markers and slingshots are prohibited on lands managed by the National Park Service. The violation could carry a fine of up to $5,000 and up to six months in prison.

“Defacing or altering the NPS landscape, no matter how small, is against the law,” said Jeff Filosa, the park’s acting chief ranger. “It diminishes the natural environment that millions of people travel the world to enjoy. ”

Authorities have tried to protect the lands and species in the national park in Southern California, which has endured hardship in recent years. The park, which is larger than Rhode Island, draws visitors for its spiky Joshua trees, a signature sight throughout its dramatic desert landscape. The Joshua tree, a yucca, can live on average for 150 years and can grow to 40 feet high. Scientists say, however, that the species is facing threats from changing climate, invasive grasses and human development.

Wildfires in 2020, which burned large sections of the Mojave Desert, killed more than 1 million Joshua trees. Several of the trees were also cut down and the park was vandalized during a partial government shutdown in 2019 that left just a skeleton crew of park staff on duty. Visitors spray-painted graffiti in the park, toppled gates and posts, and carved unauthorized paths through pristine desert, conservationists said.

In 2021, a California couple were fined $18,000 for clearing 36 protected Joshua trees just north of the national park to make space for a new home.

This article originally appeared in The New York Times.