Members of the National Park Service and contractors place a tube into the Lincoln Memorial Reflecting Pool, as the pool is cleaned of algae, Tuesday, June 16, 2026, in Washington. (AP Photo/Jacquelyn Martin)

WASHINGTON (AP) — President Donald Trump on Saturday announced that federal authorities had made “multiple arrests” of people he said were vandalizing the Reflecting Pool as he struggled to explain why the $14-million-plus rehabilitation project he launched for the nation’s 250th anniversary seemingly backfired.

Trump said his predecessors had let the pool turn an algae-stained green and that he’d line it with “American flag blue” so it better reflected the Washington Monument. But after the new pool was unveiled, its blue tinge quickly became a familiar green. Workers treated it with chemicals to kill the algae, but then the painted blue lining on the bottom began to peel.

On Friday night, Trump posted about the pool.

“We’ve had some real problems with Vandalism at the beautiful Reflecting Pool,” he posted on his social media site Friday night. “Just like three days ago, they destroyed the grass outside of the Pool, they’ve also done everything possible to hurt the inside surface that was just installed.”

Agencies responsible for law enforcement and upkeep on the National Mall — the U.S. Park Police, National Park Service and Interior Department — did not respond to requests for comment. Trump on Saturday followed up by posting that Park Police “have arrested multiple individuals for vandalizing our Nations magnificent Reflecting Poll,” correcting his spelling to “Pool” later.

He went on: “Who would do such a thing? These are very serious crimes having to do with the destruction of National Monuments. Years in jail!”

Trump later acknowledged in a post that the Reflecting Pool will need to be repaired, yet again, to restore it to “an equal level of Beauty” as before. “We met with contractors today, will probably be forced to release and drain much of the water in order to do the necessary repairs, but will have them done as quickly as possible,” he wrote.

One man arrested was David Hearn, 67, of Bethesda, Maryland, who owned a company that made composite used to build watercraft. He said he stopped by the pool during his 64-mile bike ride Friday to see what was going on.

After placing his hand in the pool, he was detained by National Guard troops and Park Police for five hours before being released Friday night.