NEW YORK - Tens of thousands of protesters gathered in New York and Washington on Saturday, stepping up demonstrations across the United States demanding justice for black men killed by white police.
The rallies in the US capital, New York, Boston and in several Californian cities were among the largest in a growing protest movement sparked by the killing of unarmed black teenager Michael Brown in Ferguson, Missouri on August 9.
Grand jury decisions not to prosecute the white officers responsible for 18-year-old Brown's death and a fatal chokehold on New York father of six Eric Garner in July, have triggered weeks of protests.
A sea of demonstrators shut down parts of Manhattan and Washington's Pennsylvania Avenue that leads to the Capitol with cries of "No justice, no peace!" "Justice Now!" and "The whole damn system is guilty as hell!"
Though police in Washington did not provide an estimate of the crowd size, it appeared far larger than the 5,000 people organizers initially said they'd expected.
In New York, police said approximately 25,000 took to the streets. The organizers tweeted that 50,000 people turned out. Their Facebook page had said that 48,000 would take part before the rally began.
The mixed crowds of black and white mobilized many young people but also families, children, parents and the elderly.
They held aloft banners proclaiming "Stop racist police" and "I can't breathe" - the last words uttered repeatedly by Garner, as police wrestled him to the ground for allegedly selling untaxed cigarettes in New York's Staten Island.
A string of deaths at the hands of officers, including that of 28-year-old Akai Gurley in Brooklyn, have inflamed resentment against police tactics in the United States and distrust many blacks feel toward law enforcement.
The Garner and Brown families were joined in Washington by relatives of 12-year-old Tamir Rice, who was shot dead last month by Cleveland police, and of Trayvon Martin, who was killed in Florida by a neighborhood watchman in 2012.
Garner's widow and wife took to the stage before the energized crowd.
"I am here not only for marching for Eric Garner, but for everyone's daughters and sons and nieces and nephews and dads and moms," widow Esaw Garner said.
Garner's mother Gwen Carr said the protests would continue until lawmakers respond to demands for reform.
"This is a history-making moment," she said as onlookers erupted in cheers.