WASHINGTON - More than 10,000 people poured into the nation's capital on the ninth day of protests over police brutality, but what awaited this sprawling crowd - the largest yet in Washington - was a city that no longer felt as if it was being occupied by its own country's military. 

Gone were the 10-ton, sand-colored tankers in front of Lafayette Square and the legions of officers braced behind riot shields, insisting that citizens stay away. In fact, few police were visible anywhere. And when protesters did see law enforcement - authorities in camouflage, grouped in twos or threes and seldom armed - they did not scream abuse, as many of them had in previous days.

Few of Saturday's demonstrations were choreographed, as protesters flowed from one impromptu gathering or march to another. Those who came out in Washington - and San Francisco, Chicago, Philadelphia and dozens of other cities across the country - understood that this was a moment in America when change seemed possible. They wanted to be there for it.

In city after city, both large and small, vast numbers of people clogged streets and halted traffic, circled government buildings and insisted that the leaders of their communities do more to protect the lives of black men and women.

The cause even led to flares of tension among Washington's protesters, with some embracing a party atmosphere while others furiously spray-painted "Defund The Police" in giant yellow letters a block from the city's "Black Lives Matter" display.

Early in the day, though, they were united. As George Floyd was being memorialized in his North Carolina hometown 340 miles south, the crowd in the District packed into six blocks along 16th Street NW to honor his life and condemn his death in police custody.

"No justice!" they chanted. "No peace!"

But the man in whose direction they shouted couldn't hear them. Nearly two miles of metal fencing now surrounded the White House, as if it had been locked in a cage, and inside, President Donald Trump was raging.

He retweeted himself, sharing a message from the day before in which he described District of Columbia Mayor Muriel Bowser as "grossly incompetent, and in no way qualified to be running an important city like Washington, D.C."

An hour later, nearly to the minute, Bowser, a Democrat, stood on the stretch of 16th she'd had painted with "Black Lives Matter" and named in the movement's honor.

She denounced Trump administration officials for authorizing federal officers to fire chemical irritants and rubber bullets at peaceful protesters, clearing them from Lafayette Square so the president could get his photo taken with a Bible in front of St. John's Episcopal Church. Now, on the section of fence there, hung protest signs, an American flag, and a torn yellow strip of police tape that read "Crime Scene."

"Today we say no," Bowser told the crowd. "In November, we say next."

Nearby, Nile Joyner-Willey, 4, sat on her father's shoulders, wearing a rainbow-colored tutu. She held a Black Lives Matter sign as her father, John Willey, 37, who lives in the District, gently bopped her up and down. This was the first day the family had attended the protests and the first day that Nile's parents had talked to their daughter about racism.

"Why are so many people taking my picture?" she asked her mother.

"Because you give people hope," answered Krystle Joyner, 34. "We're doing this for you."

As they'd done all week, the protesters started near Lafayette Square, but also spread throughout the city. They marched down U Street's historic Black Broadway and past Chinatown's brightly painted Friendship Arch. They gathered on the Capitol lawn, beside the Mall's Reflecting Pool and under the bronze Joan of Arc statue in Meridian Hill Park. They knelt beneath the folded granite arms of the Rev. Martin Luther King Jr. and at the feet of Abraham Lincoln.

Their freedom to roam, unimpeded by police, was by design. Almost all District officers were working or on call, a city official said, but they stayed away from demonstrators as much as possible. With a swath of downtown cut off to traffic, it made it easier for police to monitor the demonstrations and easier for protesters to get around.

A buzz overhead, however, was a reminder of how different these streets had been just a few days earlier, when National Guard helicopters flew as low as a two-story building, scattering broken glass as they terrified the protesters and journalists beneath them.

"The battlespace" was how Defense Secretary Mark Esper had described the city, but the resulting shows of force meant to send a clear message to protesters - stay home - had inspired them to do the opposite. By Saturday, the battle space had morphed into what felt like a carnival.

Some in the crowds - which exceeded 10,000, as people came and went for hours - took off their shoes, revealing feet red and swollen from past days' marching. Kids played in the water, splashing their parents. A father helped his daughter clamber onto an electric scooter, hopped on beside her, and took her for a slow ride around the rim of the Reflecting Pool, explaining Lincoln's fame as he did so.

On 16th Street, children followed their parents to ice cream trucks. A teenager blew bubbles into the crowd. The music thumped all day, from speakers hauled in and running on generators. Many seemed less worried than in previous days about the pandemic still killing so many people of color, with decidedly fewer protesters wearing masks or squirting their hands with hand sanitizer.

The day's activists included a group of Sikhs carrying cardboard signs and two men, both middle-aged and white, who drove 665 miles from Nashville because they compelled to do something. Lawyers came out, as did white lab-coated doctors and nurses in turquoise scrubs. A pair of 26-year-old black women drove up from Charlotte but didn't tell their parents. A trio of cousins in their 30s - one black, one biracial and one white - traveled from Baltimore, where they had attended the Freddie Gray protests five years ago. An 82-year-old black man who witnessed the 1968 riots in the District watched it all on Saturday from a folding chair, and a 2-year-old did the same in his green stroller.

"Don't shoot me," read the handwritten message on the boy's hat.

They moved around downtown in clumps, making stops to do the wobble in the streets, to pause for a free hot dog or Gatorade, to stand where Trump stood in front of the church.

"We have effectively surrounded the White House," one man said on his phone.

"I think it's officially under siege," another protester said.

As go-go music blared from a truck at the center of 16th and I streets, where five days before protesters had run scrambling from chemicals and cavalry, a fury grew among a faction of onlookers. They watched as hundreds of others pressed around the truck, shimmying and sweating and snacking.

The Washington Post's Michael E. Ruane, Perry Stein, Justin Wm. Moyer, Rachel Weiner, Michelle Boorstein, Justin George, Clarence Williams, Freddy Kunkle, Rachel Chason, Michael E. Miller, Kyle Swenson and Marissa Lang contributed to this report.