WASHINGTON – The National Park Service removed graffiti and repaired monuments outside Union Station in Washington, D.C., after protesters damaged statues and a fountain on Wednesday as they gathered in the city to condemn the visit of Israeli Prime Minister Benjamin Netanyahu.

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Thousands of protesters filled the streets of downtown Washington, carrying signs with messages such as “Arrest Netanyahu” and “End all U.S. aid to Israel.” Groups waved Palestinian flags and chanted “Free, free Palestine” and marched to the U.S. Capitol.

Outside Union Station, protesters removed American flags and raised Palestinian ones instead. The Columbus Memorial Fountain in the circle in front of the station was daubed with the words “Hamas is coming” in red paint. Other monuments, such as the Freedom Bell and various statues, were also damaged. FOX 5’s Stephanie Ramirez says police are preparing for more possible protests on Thursday.

US Capitol police used pepper spray after some protesters said they became “violent” and “disobeyed” requests to step back from the police line.

Nine people were arrested across Washington, including four on suspicion of attacking a police officer outside Union Station.

While many protesters condemned Israel, others expressed their support and urged Netanyahu to negotiate a ceasefire in the war with Hamas and release the hostages still held by the militant group.

The Associated Press contributed to this report.