Some protesters held signs that read, “No bombs on Iran” and “No New US War in the Middle East.”
Less than a kilometre away, near the World War I Memorial, a group of people waving American and Israeli flags chanted, “Thank you Trump”, appearing to celebrate the strikes.
Earlier in the day, the US President told the Washington Post the strikes were an effort to bring “freedom for the people” in Iran.
The protests in the US capital joined demonstrations that erupted in New York, Chicago, Denver and other US cities, as well as abroad.
In New York City, where several hundred people marched through Midtown Manhattan, organisers described the demonstration as just the start of a sustained movement to push back against the attack on Iran.
“I’m sick to my stomach about us going into another war,” said Aisha Jukaku, 41, an Indian American who is also Muslim.
Fanaeian, an organiser with the Freedom Road Socialist Organisation, helped co-ordinate the protest near the White House with leaders from other groups, including 50501 DC and Code Pink.
They initially gathered near 16th and H streets NW by Lafayette Square before marching through the city.
People wave US and Iranian pre-1979 Islamic Revolution flags during a rally expressing support for US and Israeli military action against Iran’s Islamic Republic government in Atlanta, Georgia. Photo / Elijah Nouvelage, AFP
“No hate, no fear, Iranians are welcome here,” many in the crowd chanted. “From DC to Iran, stop the war, stop the bombs,” others said in unison.
“Americans have made it clear that they do not want another war,” Mimi Ziad, a 27-year-old with the Palestinian Youth Movement, said in a speech from the bed of a pick-up truck.
Ziad and other demonstrators drew comparisons between the strikes on Iran and involvement by the US military in other conflicts in recent years.
As the crowd swelled and began to march, Secret Service agents and police officers were on patrol, with some officers blocking roads to let demonstrators pass through the streets.
DC police said earlier that while there were no known threats to the city, the department is “prepared to increase our presence as needed”. The department said it was co-ordinating with local, state and federal partners.
Metro Transit Police said there will be an increased presence at rail stations in the District for the next several days “in response to military operations abroad”.
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