Anthony Peltier/iStockBy ADIA ROBINSON and KIARA BRANTLEY-JONES, ABC News

(WASHINGTON) -- Thousands seeking criminal justice reform gathered at the National Mall on Friday under the rallying cry "Get Your Knee Off Our Necks," a reference to the manner in which George Floyd was killed while in police custody in May and reminiscent of the 1963 March on Washington.

"We've come, like Dr. King came 57 years ago, to say we're tired of broken promises," Rev. Al Sharpton said at the march on Friday. "There's a sense of urgency now. We need national legislation to deal with this."

The reverend said now is the time for change.

"It's time we have a conversation with America," he continued. "We need to have a conversation about your racism, about your bigotry, about your hate, about how you would put your knee on our neck while we cry for our lives. We need a new conversation."

Civil rights and social justice activists addressed the crowd and delivered speeches from the steps of the Lincoln Memorial, demanding meaningful action in ending systemic racism. Speakers also called for the U.S. Senate to pass H.R.7120, known as the George Floyd Justice in Policing Act. The bill, approved by the House but not by the Senate, would address issues linked to policing practices and law enforcement accountability.

"We must answer the call of institutional racism ... now, today, this attack on us as people of color, who died on the battles of warfare, who have died on the streets for civil rights, it will stop today," said Rep. Sheila Jackson Lee, D-Texas. "We will heal the nation, but we will not stop until the nation knows Black lives matter and reparations are passed as the most significant civil rights legislation of the 21st century."

Joyce Beatty, vice chair of the Congressional Black Caucus, echoed a similar sentiment.

"Go vote! Go vote!" Beatty added. "Tell them to get their knees of of our necks."

Yolanda Renee King, Martin Luther King Jr.'s granddaughter, also gave an impassioned speech about the challenges facing her generation.

"We are going to be the generation that dismantles systemic racism once and for all, now and forever," she said. "We are going to be the generation that ends poverty here in America, the wealthiest nation on Earth."

She added: "We stand and march for love and we will fulfill my grandfather's dream."

Martin Luther King III, who helped lead Friday's march, spoke about current injustices.

"We're marching to overcome what my father called the triple evils of poverty, racism and violence," he added, listing challenges that disproportionately affect Black and Latino communities, including the coronavirus pandemic, unemployment, police brutality and attacks on voting rights.

He called on attendees to exercise their right to vote in the upcoming election.

"We must vigorously defend our right to vote because those rights were paid for with the blood of those lynched for seeking to exercise their constitutional rights," King said.

He told ABC News' "2020" in an interview scheduled to air on Friday that normally there wouldn't be a demonstration on the 57th anniversary of his father's historic march.

"But because of what is going on," the oldest son of Martin Luther King Jr. said, "the climate in this nation -- more civil rights demonstrations we've seen in our nation and really throughout the world that are finally acknowledging that Black lives matter -- when you realize the reasons why, police brutality and misconduct is still occurring, it is beyond time for immediate action."

"We all saw some things begin to move a short period of time after, tragically, George Floyd was killed, but we haven't made the kind of steps that we need to, certainly not at the national level," he added.

Family members of Black Americans who were victims of police brutality spoke to attendees at the March on Washington.

Wanda Cooper-Jones, the mother of Ahmaud Arbery, a 25-year-old Black man chased and shot to death while jogging in Glynn County, Georgia, spoke to attendees.

"I'm carrying a very broken heart," she said. "But also a grateful heart that God chose my son, Ahmaud Arbery, to be a part of this most huge movement."

"I do believe that if we continue to stand and fight together, that we will get change," she added.

Tamika Palmer, Breonna Taylor's mother, walked up to the podium as the crowd chanted, in call-and-response style, "Say her name! Breonna Taylor!"

Palmer began her speech by thanking supporters who have been fighting for justice for her daughter.

"What we need is change, and we're at a point where we can get that change, but we have to stand together. We have to vote," Palmer said.

Then the family members of George Floyd addressed the crowd.

Philonise Floyd, his brother, was greeted by repeated "George Floyd!" chants from the crowd.

"I wish George were here to see this right now. That's who I'm marching for," Philonise Floyd said. "I'm marching for George, for Brianna, for Ahmaud, for Jacob, for Pamela Turner, for Michael Brown -- Trayvon and anybody else who lost their lives."

He was joined by his sister, Bridgett Floyd, who also spoke. She urged them to stand against injustice and to reflect on how future generations will look back on their actions today.

"We're here right now and have the power to make it happen," she said. "My brother cannot be a voice today -- we have to be that voice, we have to be the change and we have to be his legacy."

Jacob Blake Sr., the father of Jacob Blake, who was shot in the back by police in Kenosha, Wisconsin, spoke to the crowd as well.

In the wake of the shooting that left his son paralyzed, Blake Sr. encouraged attendees to "stand up" against injustice. He also expressed his love for supporters. With his fist clenched and raised in the air, he chanted: "No Justice!" and the crowd responded, "No peace!"

Blake said that he attended Friday's March on Washington because he had "a duty" to show support.

"But we're gonna stand up. Every Black person in the United States is gonna stand up. We're tired!" he said. "And we're not taking it anymore, I ask everyone to stand up. No justice, no peace!"

Letetra Wideman, Jacob Blake Jr.'s sister, also addressed the crowd, calling for Black people to unify.

"We will not be a footstool to oppression," Wideman said. "Black America, I hold you accountable. You must stand. You must fight, but not with violence and chaos -- with self love."

Citing "group economics," she called on Black children to "read, learn, grow and live, and question everything."

"Stand up, Black men!" she added. "Educate yourself and protect the Black family unit."

The "Get Your Knee Off Our Necks" March comes toward the end of a summer of unrest sparked by more Blacks being killed or severely injured by police. Floyd, 46, died after Minneapolis police officer Derek Chauvin kneeled on his neck for more than eight minutes. Chauvin was fired and now faces murder charges.

Protesters have called for the arrest and prosecution of the Louisville, Kentucky, officers involved in the March shooting of Breonna Taylor, a 26-year-old EMT who was shot at least eight times when plainclothes officers fired "blindly" into her apartment as they executed a no-knock warrant, alleges a lawsuit by Taylor's mother.

Blake, 29, was shot by a police officer in Kenosha, Wisconsin, on Sunday night. According to Blake's family, he was shot seven times in the back and is now paralyzed from the waist down.

The Department of Justice identified the officer as Rusten Sheskey Wednesday.

Due to COVID-19 concerns, all participants are required to wear masks and get their temperatures checked before entering the event. While buses are bringing participants in from outside of the region, the organizers are discouraging people living in states on D.C.'s mandatory quarantine list from traveling there for the march.

"We are tired of the mistreatment and the violence that we, as Black Americans, have been subjected to for hundreds of years," Sharpton said in a statement before the event. "Like those who marched before us, we are standing up and telling the police, telling lawmakers, telling the people and systems that have kept us down for years, 'Get your knee off our necks.'"

Sharpton announced the march in June during his eulogy at Floyd's Minneapolis memorial service. It occurs on the 57th anniversary of the original March on Washington and in conjunction with the NAACP's virtual March on Washington.

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