Authorities did not say how long the restoration process would take.
The Washington Monument was temporarily closed, police said, after a man vandalized the national landmark with profanities and red paint.
The incident occurred on Tuesday evening, when the base of the historical monument was splashed with red paint and an obscene message was written across the side of the structure.
"The United States Park Police has an adult male in custody for vandalizing the base of the Washington Monument with paint," the United States Park Police said in a statement obtained by ABC News. "The area at the base of the monument will be temporarily closed."
U.S. Park Police identified the suspect as Shaun Ray Deaton, 44, of Bloomington, Indiana, and charged him with trespassing, tampering and vandalism in connection with the incident, it said Wednesday. The investigation is ongoing and U.S. Park Police said there may be additional charges against Deaton.
It's unclear what the motivation was for the vandalism or if the message scrawled on the base of the monument was targeting anybody specific.
National Park Service conservators are working to restore the monument. On Wednesday morning, its preservation crew was removing the top layer of paint. Pigment that had seeped into the stone will be treated with "many rounds of cleaning product application," it said.
"A week of sunlight will also help return the monument to its usual impressive state," the National Park Service said.
Authorities did not say how long the restoration process would take or how long the tourist attraction is expected to be closed to the public.
The Washington Monument was open again Wednesday morning.
The Washington Monument, completed in 1884, stands at 555 feet tall and was the tallest structure in the world from 1884 to 1889 before it was overtaken in height by the Eiffel Tower in Paris. The obelisk is named after the first president of the United States and attracts over 600,000 visitors a year.
ABC News' Beatrice Peterson contributed to this report.