Protesters demanding the US stop military aid to Israel hoisted Palestinian flags and burnt American ones outside Washington's Union Station in demonstrations against a visit on Wednesday by Israeli Prime Minister Benjamin Netanyahu.
Less than a mile away, police used pepper spray on some of the thousands of pro-Palestinian protesters who gathered outside the US Capitol while Netanyahu spoke to Congress.
Seeking the support of US lawmakers for Israel's war in Gaza, Netanyahu sketched a vague outline of a plan for a "deradicalised" post-war Gaza and touted a potential future alliance between Israel and America's Arab allies.
He was due to meet President Joe Biden and Vice President Kamala Harris on Thursday and former President Donald Trump on Friday.
Shortly before he began speaking, US Capitol Police said marching protesters tried crossing a blockade and did not step back when asked.
"The crowd failed to obey our order to move back from our police line. We are deploying pepper spray towards anyone trying to break the law and cross that line," police said in a statement.
"We were no threat (to police)," said Sarah Bowles, a pharmacy technician from Delaware who attended the protest and assisted protesters who were injured. One of the protesting groups said police attacked demonstrators as they marched.
Pro-Palestinian groups and university students have for months protested in the US against Israel's offensive in Gaza, a Hamas-governed enclave where health authorities say nearly 40,000 Palestinians have been killed.
Israel's military assault followed an October 7 attack by Hamas, whose militants surged into Israel, killing 1,200 people and taking around 250 hostages, according to Israeli figures.
Despite mediation efforts by the United States, Qatar and Egypt; Israel and Hamas have yet to forge a permanent ceasefire.
Netanyahu, while addressing Congress, said he had a message for the protesters.
"When the tyrants of Tehran who hang gays from cranes and murder women for not covering their hair are praising, promoting, and funding you, you have officially become Iran's useful idiots," he said, using a Cold War-era term for people who are manipulated for a political agenda.
Protesters deny such charges and say their demonstrations are a response to the humanitarian crisis in Gaza where nearly the entire 2.3 million population have been displaced.
A stage at the protest site near the Capitol was decked with banners, including one that declared the Israeli leader a "Wanted War Criminal" in reference to an arrest warrant sought by International Criminal Court prosecutors. Netanyahu denies war crimes allegations.
Nearby, demonstrators placed nearly 30 human-size cardboard coffins wrapped in Palestinian flags. Traffic was barred from several roads near the Capitol.
"I want all aid (to) be suspended to Israel due to its actions in Gaza," said Bradley Cullinan, who said he travelled to the area from Columbus, Ohio, 400 miles (640 km) away.
Oscar-winning actor Susan Sarandon took to the stage and condemned the death toll in Gaza. "No one is free until everyone is free," Sarandon said.
Dozens of Democratic lawmakers skipped Netanyahu's speech to Congress, expressing dismay over the deaths and the humanitarian crisis in Gaza where nearly all of its 2.3 million people have been displaced.
Members of an ultra-Orthodox Jewish group carried Palestinian flags and signs reading "Free Palestine" and "Anti-Zionism is not antisemitism," while a group of younger protesters danced to Arabic music and carried large banners reading "Stop Arming Israel" and "Stop War Crimes in Gaza."
ICC prosecutors say there are reasonable grounds to believe Netanyahu and Israeli Defence Minister Yoav Gallant as well as Hamas leaders Yahya Sinwar, Mohammed Al-Masri and Ismail Haniyeh, bear criminal responsibility for alleged war crimes and crimes against humanity.
