Women's March in Washington: Live updates

A day after Donald Trump was sworn in as the nation's 45th president, thousands of people are descending upon Washington, D.C., to participate in Saturday's Women's March.

The march — which kicked off with a rally at 10 a.m. featuring speakers and musical acts — is based on a mission that the rhetoric of the 2016 election cycle "insulted, demonized, and threatened": Americans, leaving communities “hurting and scared.”

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The Washington, D.C., Homeland Security and Emergency Management Agency estimates as many as 400,000 people could attend the march, though organizers believe the number of attendees is even higher.

Organizers have tagged the march as a nonpartisan opportunity for people to "stand together in solidarity with our partners and children for the protection of our rights, our safety, our health, and our families — recognizing that our vibrant and diverse communities are the strength of our country."

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Critics contend that the march is a protest against Trump’s presidency, ABC News reported. Several groups, which opposed Trump’s candidacy, have joined the Women’s March as partners, including the American Civil Liberties Union, Amnesty International, Emily’s List, Planned Parenthood, GLAAD and the Muslim Women’s Alliance all signed on as the event grew in size.

Organizers said one of the goals of the march is to tell the new administration that on Day One, “women's rights are human rights.”

Prior to the march, a three-hour rally will be held on the National Mall with musical headliners Janelle Monae, Questlove, and Grimes, along with celebrity speakers that include America Ferrera, Angela Davis, Gloria Steinem, Ashley Judd, Melissa Harris-Perry, and Michael Moore. Planned Parenthood president Cecile Richards is one of the keynote speakers.

Rallies also are being held worldwide. According to Buzzfeed, thousands of marchers gathered Saturday morning in Sydney, Australia. Marchers in Australia carried signs that contained slogans like "Feminism is my Trump card," and "Women of the world unite."