For 8 minutes and 46 seconds in the sweltering heat of a Washington summer day, hundreds of people knelt on the pavement around the Martin Luther King Jr. Memorial. They bowed their heads in silence. They marked the amount of time that George Floyd spent with a Minneapolis police officer’s knee on his neck.

Seven days after protesters first descended on the nation’s capital for moments like this, the uprising of the angry, exhausted and fed up showed Thursday that they are far from finished. Protesters held a “die-in” at the White House and a march to Washington National Cathedral. They accepted the risk of coronavirus and got drenched in a nighttime thunderstorm. They doused their hands in sanitizer and led their children through the crowds.

“People are listening,” said ­Ciyanne Zewdie, an 18-year-old high school student returning to protest for a second day. “It’s like there’s been a knife stabbed in our back. It’s only been moved three millimeters. It’s going to take a long time to be out all the way.”

The demonstrations have evolved drastically since Monday, when a peaceful assembly was disrupted by an aggressive law enforcement offensive and more than 200 arrests were made, many for looting. By Thursday, the streets surrounding the White House had become an orderly ecosystem with a predictable routine and a block party atmosphere — until a thunderstorm moved in.

Two National Guardman were injured by a lightning strike that hit Lafayette Square near midnight. They were taken to the hospital with serious but non life-threatening injuries, according to a spokesman for D.C. Fire.

Earlier in the day, hundreds of protesters gathered beside the tall fences surrounding Lafayette Square around 4 p.m. On cue, medics started setting up first aid stations beneath trees and under awnings, ready to receive patients in the relief-giving shade. A man unpacked a full drum set, blue and sparkling. Someone placed cardboard boxes labeled “TRASH” and “BASURA” on curbs. Snack stations offered water, coffee, Cheezits, sandwiches, quesadillas and voter registration forms.

Reginald Guy arrived with a grill, a fold-up serving table and 100 hot dogs. Someone saw him setting up and donated hamburger meat to the menu. On Friday, he planned to return with sides and vegan options.

“This is not a granola bar moment,” Guy said just before dousing his coals with lighter fluid. “We’re not hiking. This is not a game.”

On this night, no curfew would send the people home early. After Wednesday demonstrations ended with zero arrests, police injuries or damage to police property, D.C. Mayor Muriel E. Bowser didn’t impose another.

“Moving forward over the next couple of days, we expect more of the same,” D.C. Police Chief Peter Newsham said Thursday.

While pleased with the continued calm, Bowser and Newsham denounced the heavy presence of federal law enforcement around the city, blocking off huge swaths of downtown and access to many monuments. National Guard units from around the country have been deployed to the District, along with agents from the FBI, Drug Enforcement Administration, U.S. Marshals Service and the Federal Bureau of Prisons. Attorney General William P. Barr is orchestrating the federal law enforcement activity from a command center in Chinatown.

“We want troops from out of state out of Washington, D.C.,” Bowser said. “I’m also concerned that some of the hardening that they’re doing may be not temporary.”

Bowser and city officials had complained that federal officials expanded the perimeter around the White House on Wednesday to include half a city block north of Lafayette Square. By Thursday, the troops had retreated back to the square, behind the tall chain link fence. But the fence had been extended down 17th Street and Constitution Avenue, blocking access to the Ellipse, the 52-acre park adjacent to the White House and maintained by the National Park Service. Heavy concrete barriers added a second layer of protection.

As crowds assembled at Lafayette Square — smaller in number than the days before — officers stayed well back from the fencing, a marked contrast from Wednesday, when protesters had spent much of the day face-to-face with members of the National Guard wielding shields and batons. They lounged on benches and watched a squirrel scurry past. One pointed, gesturing to his neighbor. 

“Jesus, don’t they have anything better to do,” a protester marveled. 

“Our tax dollars at work,” said another. 

“You know, the White House is the people’s house, and it makes me so mad we’re being kept from it, behind this fence,” said Regina Watson, 35, who lives in Deanwood. “Our ancestors built that house. Brick by brick. That’s our house. Donald Trump is just a guest.”

Watson hadn’t attended the previous days’ demonstrations, when police loosed chemical gas and rubber bullets on crowds of protesters. She was waiting for the violence to subside. She was among many who attended the demonstrations for the first time Thursday, either because they felt the risk of violence had subsided, or because they’d decided the other risk — of contracting the coronavirus in the crowd — wasn’t enough to make them stay home.

Jillian Ross, a 26-year-old Howard University medical ­student, well understood the seriousness of the pandemic. But she said she was also acutely aware that when her forebears stood up for their rights half a century ago they also faced immediate dangers: overtly racist elected officials, fire hoses and vicious dogs of the kind President Trump has so far only threatened to use. 

For that reason, Ross said, “it was an easy decision to come out here.”

Tuesday Cook Headley, 43, a Maryland surgeon, brought her 7-year-old daughter with her to witness the protest and let her know that she needs to be a part of bringing about change in the country.

Cook Headley said her daughter had been stuck at home for nearly three months because of the pandemic.

“We’ve kept her safe, but this is injustice that calls us out. We want to stay in to stay safe, but we’re not safe when innocent black men and women are murdered in the street or in their home,” she said. “The anger and frustration of more than 400 years of injustice to black people in this country has become too much. It’s been too much.”

“And we’re not standing for this anymore!” her daughter interjected.

“That’s right!” her mother said with a laugh behind her mask.

Long days of repeated marches and chants seemed only to invigorate many demonstrators, such as Jada Wallace, 18, who ventured downtown from Germantown, Md., three days in a row — every time, alone. 

“I want to keep on going for as long as I can,” she said. “I don’t want this urgency to go away — even though I know it will.” 

Organizers hoping to keep that day from coming soon spread the word about multiple demonstrations planned for Saturday, hoping to attract visitors from beyond the D.C. region. And during a memorial service Thursday for George Floyd, the Rev. Al Sharpton announced plans for an Aug. 28 demonstration in the nation’s capital on the 57th anniversary of the March on Washington.

“That’s where your father stood in the shadows of the Lincoln Memorial and said, ‘I have a dream,’ ” Sharpton said, pointing to Martin Luther King III in the audience. “We need to go back to Washington and stand up — black, white, Latino, Arab — in the shadows of Lincoln and tell them, ‘This is the time to stop this.’ ”

As he spoke, hundreds were on their way to do just that. Half the protesters broke off from Lafayette Square and marched to the famous marble steps, which were blocked by barricades, to kneel, chant and, like so many times before, say Floyd’s name.

At the White House, Emma Mann hoped to educate those around her about all the people whose stories had ended like Floyd’s but who disappeared from the headlines.

The 34-year-old from Arlington, Va., printed off photos of black women reported to be killed by police. She’d intended to print only a few but grew overwhelmed as she worked — and the poster she held above her head Thursday was crammed with photos of 19 women.

In the upper right corner were four pictures of Mann’s cousin. Gynnya McMillen, 16, died in a juvenile detention facility in Kentucky.

“What happened to her?” asked a man walking by, pointing to a face in the middle of the poster.

“She was responding to a 911 call,” Mann said, “and police thought she was the aggressor.”

The man moved on, shaking his head, but Mann stayed. It was her first day out protesting in the District. She was prepared to stay all day.

But around 8 p.m., dark clouds appeared over the White House and the Lincoln Memorial, quickly followed by slashing strikes of lightning. Many grabbed their friends and started running for their cars or the refuge of an awning. Some frantically searched for Lyft rides. But dozens more stayed, even as the rain began to fall, then pelt, then soak them. On the other side of the fence, officers used their shields for cover.

“See, now we’re making them stand in the rain!” a man told to his friend.

The YG song “F--- Donald Trump” blasted through a speaker. The protesters held up their signs and started to dance. Now they had a new chant, for the rain, for the police, for the country: “We’re not leaving, we’re not leaving, we’re not leaving.”

They stayed for hours. Dozens marched through the city, ending up, after 11 p.m., at the Martin Luther King Jr. Memorial once again.

Someone turned on a speaker and began playing a recording of King’s “I have a dream” speech.

The protesters knelt, raised their fists, and listened.

“One hundred years later, the Negro is still languished in the corners of American society and finds himself an exile in his own land,” King said.

After the speech ended, the rain returned. The group stood up and kept marching.

Teddy Amenabar, Joe Heim, Justin Jouvenal, Marissa Lang, Fenit Nirappil, Paul Schwartzman, Patricia Sullivan, Rebecca Tan, Freddy Kunkle, Clarence Williams and Julie Zauzmer contributed to this report.