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Kamala Harris has accepted her historic nomination as the US Democratic party's vice-presidential candidate, running with Joe Biden for the White House.
The California senator, the first US black running mate on a major-party ticket, assailed US President Donald Trump's "failure of leadership".
She said the Republican leader "turns our tragedies into political weapons".
Mr Biden and Ms Harris will challenge Mr Trump and his Vice-President Mike Pence in the election on 3 November.
What did Harris say?
"We're at an inflection point," Mr Biden's running mate said as she attacked Mr Trump, speaking live from a largely empty hotel ballroom in his hometown of Wilmington, Delaware.
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"The constant chaos leaves us adrift. The incompetence makes us feel afraid. The callousness makes us feel alone. It's a lot.
"And here's the thing: We can do better and deserve so much more.
"We must elect a president who will bring something different, something better, and do the important work."
She highlighted the disproportionate impact of the coronavirus on people of colour, moving on to the racial justice protests that have convulsed the nation in recent months.
"There is no vaccine for racism. We've gotta do the work," she said listing the names of unarmed black Americans who have been killed by police.