Visitors to a park in Washington state were shocked to see turtles tagged with large swastikas painted on their shells.

The turtles were spotted in Gene Coulon Memorial Beach Park in Renton, just outside Seattle. Local police said they’re aware of the turtles and have tried to capture them, but “so far they’ve evaded apprehension,” reported the Seattle Times.

Officials reportedly think they were pets that had been released. Police have said they’re not investigating the painting of the turtles, and that it wouldn't rise to the level of breaking animal cruelty laws unless the turtles were harmed.

Activist groups have planned a “Rally Against Hate” in response to the turtles being marked up with the anti-Semitic symbol.

“While it’s hard to know the intention or what the perpetrator had in mind, it seems pretty clear to us what the symbol means,” Miri Cypers, the regional director for the Anti-Defamation League, told the Seattle Times. “I think it’s a really sad and unfortunate act. Unfortunately, anti-Semitic vandalism is becoming all too common in this climate.”

Renton Parks and Trails Director Cailin Hunsaker told the paper they were working to find the turtles, and that while the animals’ well-being didn’t yet appear to be affected, they “don’t know how the paint might be compromising their health.”

Some have noted that the swastikas painted on the turtles are inverted, which could be intended to have different meaning than the Nazi-era symbol. But even if that were the case, it’s still a swastika, and still upsetting to many.

"Some of the passerbyers are like, ‘Wow, what's that swastika?’” said park visitor Phoukham Kelly Bounkeua to KIRO/CNN. “Kind of sits with you uncomfortably, with that feeling and so it's in the sort of shock value."