The sister of George Floyd, whose death in police custody sparked months of racial turmoil across the US, has urged civil rights protesters to "be his legacy" as thousands gathered for a rally in Washington DC.
"My brother cannot be a voice today," said Bridgett Floyd. "We have to be that voice, we have to be the change".
Ms Floyd was one of several relatives of Black Americans harmed or killed by police to address the event commemorating a historic 1963 civil rights march.
Speakers demanded racial justice and urged people to vote. Jacob Blake Sr, whose son was shot in Wisconsin, told the rally they were holding court on racism in America - and the verdict was "guilty, guilty, guilty!"
Thousands of people gathered in Washington DC for the event that commemorated the 1963 civil rights March on Washington and in protest at police violence.
Called the ‘Commitment March: Get Your Knee Off Our Necks’ - a reference to the murder of George Floyd, who died in May after a policeman knelt on his neck for several minutes - it follows renewed protests over the police shooting of Jacob Blake.
The event brought together generations of activists to call for police reform and to urge Americans to vote in November's general election. It was organised by civil rights leader Reverend Al Sharpton and Martin Luther King III - the eldest son of Mr King Jr.
The families of Black Americans shot or killed by police spoke at the same site where Martin Luther King Jr delivered his I Have a Dream speech. The 1963 March on Washington was a seismic event in US history, credited with spurring the passage of the Civil Rights Act outlawing segregation the following year.
Some 250,000 supporters packed the 1.9 miles (3 km) strip from Lincoln Memorial to the Washington Monument, making it one of the largest political gatherings the country had ever seen.
Rev Sharpton announced the 2020 march - which falls on the 57th anniversary of the 1963 event - at Mr Floyd's memorial service in June. His organisation, the National Action Network, worked with Mr King III to convene the rally.
"The nation has never seen such a mighty movement, a modern day incarnation of what my father called the coalition of conscience," said Mr King III.
"And if we move forward with purpose and passion, we will complete the work so boldly began in the 1960s."
The event comes in the wake of at times violent protests over Mr Blake's shooting that have left two dead in Kenosha, Wisconsin. Mr Blake was shot and injured by police.
Since Mr Floyd's death in May, marches in support of the Black Lives Matter movement and against racism and police brutality have swept the US and the globe.
Speakers during the morning's programming included congresswoman Ayanna Pressley, who paid tribute to the activism of Black Americans of the past whose "sacrifice and self-determination shaped history and brought us to this moment".
"We are Black with a capital B," she said. "We are the manifestation of the movement. We are a symbol of social, political and cultural progress."
Other presenters included a young activist who called for an end to the gun violence that plagues Black communities, and representatives from unions, gay rights groups and Hispanic activism groups, who expressed solidarity with the Black Lives Matter movement.
Democratic vice-presidential nominee Senator Kamala Harris addressed the rally virtually.
Harris, who grew up in an activist household, paid tribute to civil rights leaders of the past.
"Let's march on for our ancestors and let's march on for our children and grandchildren," she said.
Among the initiatives on the agenda were slavery reparations, defunding police departments and investment in healthcare, housing and social services in Black communities, organisers said. It was drafted by hundreds of delegates from across the country.
