President Donald Trump’s Administration said that multiple people have been arrested for allegedly vandalizing the recently renovated Lincoln Memorial Reflecting Pool and that vandals will be prosecuted to the fullest extent of the law.

Trump on Sunday blamed vandalism for recent issues with the pool, which reopened on June 6 after over $16 million of renovations to make the pool appear “American flag blue.” The pool’s new blue paint appeared to be peeling off less than two weeks after its completion, and the pool has been plagued by an algae bloom that gave the water a green tint.

On Saturday, Trump said that vandals had poured corrosive chemicals into the pool. U.S. Attorney Jeanine Pirro told Fox News on Sunday that citations for vandalism have already been issued. Pirro said that if anyone was found to have added products to the pool to generate the algae, they could face more severe charges.

“Work will begin immediately on fixing the seriously vandalized Reflecting Pool,” Trump posted on Truth Social on Sunday afternoon. “I just inspected it, and could only say to myself, and those gathered around me, WOW, who would do such a thing? SICK, DERANGED PEOPLE! We will fix it?”

The President’s remaking of Washington, D.C., has been criticized for bypassing established preservation processes, including public consultation, and using taxpayer funds to alter historic landmarks. Democratic lawmakers also raised concerns about the awarding of a $1.74 million no-bid contract to Greenwater Services for installing an upgraded filtration system. The business is owned by a trust led by John J. Cafaro, a donor to Trump’s campaign.

ABC also reported that Atlantic Industrial Coatings was awarded an additional two payments totalling $1.54 million after the renovation project’s scheduled completion date, bringing the total to around $14.65 million for repainting. Contracting documents described the work as “PAINT LINCOLN REFLECTING POOL,” and said it was within the scope of the original agreement.

The Trump Administration has also faced backlash for other commemorative plans for the country’s semiquincentennial, including potentially placing Trump’s image on a gold coin, paper money, and passports.

TIME has reached out to the White House for comment.

Former Olympian among ‘multiple’ arrested

Three-time U.S. Olympian David Hearn was arrested on Friday after touching a strip of rubbery material in the pool, the BBC reported. The 67-year-old former slalom canoeist said the rubber appeared to have “delaminated” from the bottom of the pool.

U.S. Park Police and National Guard troops stopped Hearn and handcuffed him, a video posted online showed. Hearn denied any wrongdoing and said that he did not “destroy, rip, tear, peel, or remove any part” of the paint. Hearn said he was released on Friday night after being detained for five hours, and faces a misdemeanor charge of destruction of government property.

“It’s pretty clear that somebody high up decided to make an example of me,” Hearn said.

Trump shared on social media an article about Hearn’s arrest. Several other people were also arrested for allegedly damaging the pool, Trump said in another post.

“The United States Park Police have arrested multiple individuals for vandalizing our Nations magnificent Reflecting Pool. Who would do such a thing? These are very serious crimes having to do with the destruction of National Monuments,” Trump posted on Saturday. “Years in jail! Work will begin immediately on its repair.”

Prior to the alleged vandalism, which Trump said included a 250-foot cut into the pool’s facade, the newly opened pool “worked perfectly, including the mirror like finish, perfectly reflecting the two Great Monuments, which it never had before!”

Trump began placing the blame for the pool’s recent problems on vandalism on Friday.

“We’ve had some real problems with Vandalism at the beautiful Reflecting Pool, which sits between The Washington Monument and The Lincoln Memorial,” Trump posted on Friday. “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. No different than the chemicals that were used on the National Mall, they used something similar in the Reflecting Pool to try to destroy and demean our beautiful work.”

Trump also accused ABC reporter Jonathan Karl of “trying to rip the rubber off of the surface.” Karl had lifted up what appeared to be a piece of paint that peeled off while visiting the pool for an ABC report last week.

Prominent MAGA influencers had pointed to the possibility of “vandalism” and “sabotage” soon after the algal bloom emerged.

Algae a persistent problem in the pool

Scientists, however, have said that the pool’s conditions, especially during the summer, make it only natural for algae to bloom. That’s especially true after renovations, which could have affected the balance of nutrients in the pool, Rosalina Stancheva Christova, a professor of aquatic ecology at Virginia’s George Mason University, told NPR. The darker interior in the pool also absorbs more sunlight, making the water warmer and more likely to lead to algae growth, she added.

The algae found in the pool, belonging to the genus Desmodesmus, is not toxic or harmful, she said.

The Trump Administration previously told CNN the algal bloom was an expected “part of the normal start-up process” because residual algae had been lying dormant in the pool’s supply lines while the pool underwent construction.

Algae has been a recurrent problem for the reflecting pool since it opened, and previous fixes have been short-lived. The Barack Obama Administration oversaw a major $34 million renovation of the reflecting pool between 2010 and 2012 in an effort to stop the pool from leaking and install a filtration system to neutralize the algae. The pool was also made shallower to save water and the bottom was tinted gray to make it appear more reflective. But algae eventually resurfaced and some leaking continued, according to the Associated Press.

The installation of an upgraded nanobubbler filtration system, costing $1.7 million, was meant to prevent algae growth by cutting off its food supply. The Department of the Interior posted on X last week that “the advanced nanobubbler technology very effectively killed the algae that has plagued every Lincoln Reflecting Pool reopening—most infamously Obama’s reopening—since 1922.”

“The Reflecting Pool water is crystal clear, and our National Park Service team is now vacuuming up the dead algae resting on the bottom of some parts of the Reflecting Pool—just like the destroyed Iranian Navy resting on the bottom of the Persian Gulf,” the department said.

Reflecting pool back under repair, potentially raising costs

The reflecting pool has already undergone further repair efforts after the recent problems emerged since it was refilled and reopened in early June.

Last week, National Park Service workers began pouring hydrogen peroxide ​into the pool to treat the algal bloom.

Trump said in his Friday post that the algae is “75% gone, and the condition will soon be completely remedied.” He added that the “area that was vandalized, fortunately, is just a small area of damage, and will be fixed early next week.”

On Saturday, however, Trump said the pool would likely need to be drained, although he said the repair would be “done as quickly as possible.”