DALLAS — After a long night of chaos and uncertainty, the city is finally quiet.

Twenty blocks in the heart of downtown are blocked off by police barricades, an active crime scene where five officers were killed and six others were wounded by sniper fire amid an otherwise peaceful demonstration against police brutality.

In the hours after what appears to be the most deadly attack on police since September 11, everyday habits are suspended. The Bank of America in the center of the blockade is closed. So is the McDonald’s on the corner. Raven Bartee, who works in the area, parked her car yesterday in what is now a crime scene, and she can’t get to her house keys, her car or her daughter’s diapers.

John Collins, a lawyer who has lived in Dallas for more than five decades, watches the officers from across Lamar Street and reaches for the obvious point of comparison. Collins remembers the days after President John F. Kennedy was assassinated, just a few blocks from where he’s now standing.

“We’ll all pull together now,” he said, “but it’ll take a long time for us to heal.”

Periodically, members of the public approach police officers, offering to buy them coffee, water or anything else they might need. Naomi Baxter, a member of Mothers Against Police Brutality who attended Thursday’s protest, asks if there is anything at all she can do. The officers say they appreciate her support, and decline the offer.

Baxter has been a regular attendee at Dallas demonstrations for years. She joined the organization to protest police brutality after her cousin, Clinton Allen, was shot and killed by a police officer in 2013. Allen was unarmed, and the police officer, Clark Staller, was not indicted.

But in recent years, she said, she has seen a marked improvement in the relationship between the Dallas police force and the black community. It stands in stark comparison to the fear and distrust of police reflected in many communities, something that President Barack Obama addressed earlier this week.

“Chief Brown has really taken it upon himself to talk with the police officers, to let them know they’re here for the people, and I feel like they are,” Baxter said, trying to hold back tears. “Walking up on us with their hands on their holsters — no. They walk to us with their hands just like these officers,” she said, waving at the officers along Jackson Street.

Baxter was one of the first to arrive at Thursday’s demonstration, her tambourine in tow. She said the event was peaceful and calm until the very end, and remembered officers clearing traffic and reminding the demonstrators to stay hydrated in the Dallas heat.

“These police officers had no aggression,” Baxter said. “If they did, I would have been the first person to speak up. Because that’s what I’m about – us speaking up for what’s right.”

“They were in the right this time,” she said.

Brown said Friday morning that he was not ready to speculate on the shooters’ motives, or draw a definitive connection between the rally and the culprits. But he added that one of the snipers said he “wanted to kill white people” before being killed by a police department bomb

Shetamia Taylor, who attended the Thursday demonstration with her family, was the snipers’ only civilian victim. Taylor, who jumped on top of her sons to protect them, was shot in the leg and is expected to recover.

The long-term repercussions of the Dallas shooting have yet to be determined. The sniper attack was the third in a series of high-profile events in an emotionally charged week, after police officers killed black men in Baton Rouge, La., and Falcon Heights, Minnesota.

Alton Sterling, 37, was killed by Baton Rouge police while selling CDs outside a convenience store, while Philando Castile, 32, was killed after being pulled over for a traffic violation. Both incidents were recorded on film.

The national conversation around shootings and gun control was also electrified by the recent mass shooting in Orlando — which had the highest death toll of any shooting in modern American history — and a 25-hour sit-in led by Democrats in the U.S. House of Representatives.

But until shots rang out in the streets of Dallas Thursday night, the mood at the protest was one of sadness and support, according to several event attendees.

“This was my first protest, and at the beginning I felt so safe,” said Diya Wazirali, who attended the demonstration with her sister and cousin. “It was very peaceful — I just felt like I was part of the community, and we were all there together.”

Although the event was publicized as a protest against police brutality, the relationship between the protesters and Dallas police officers in particular was not marked by animosity, according to Sahare Wazirali.

“The Dallas Police Department has repeatedly stood in solidarity with the Black Lives Matter movement — they’ve been consistently supportive,” Sahare Wazirali said. “They’ve walked alongside marchers, and they’re one of the most active police departments in terms of making sure there’s accountability in police work.”

“We’re grieving for their families,” she added.

Over the course of the last few years, officer training has increasingly focused on de-escalation tactics, which Brown has cited as one reason the number of excessive-force complaints against Dallas officers has steadily decreased.

Early Thursday evening, the Dallas Police Department posted videos and photos of the demonstration on the department Twitter account. In one photo, smiling police officers stand beside a man holding a sign that says, “No Justice, No Peace.” In another tweet, officers filmed the the crowd as demonstrators chanted “Indict, convict, send these killer cops to jail / The whole damn system is guilty as hell.”

At sundown, just before 9 p.m., the first shots rang out, but in the din, it wasn’t immediately clear what the source of the sound was.

“I heard the shots, but I don’t think it registered in my mind — I thought something had happened to my dad’s car,” said Lexi Lewis, a Dallas highschooler who attended the event with family members. “Nobody in the car realized they were shots.”

The scene was calm, until it wasn’t. Quickly, police officers started urging people to leave the scene.

“It got quiet, and then they told us — run, run,” Sahare Wazirali said. “We’ve never run so fast in our lives.”

By midnight, the streets were largely empty, except for police officers. Officers urged civilians who were still downtown to stay indoors.

At press conferences held over the course of the night, the police chief and Dallas Mayor Mike Rawlings kept an intense calm, answering questions as a standoff between officers and one of the suspects developed in a nearby parking garage.

“The suspect has told our negotiators that ‘the end is coming,’ and he’s going to hurt and kill more of us, meaning law enforcement, and that there are bombs all over the place, in this garage and downtown,” Brown said. “So we’re being very careful with our tactics.”

Rawlings acknowledged that the situation was changing minute to minute, and encouraged locals to stay away from normally-bustling downtown Dallas until the confusion had settled.

“This is still an active crime scene, and we are determining right now how big that crime scene is,” Rawlings said.

Rawlings also commended Brown and the Dallas police force for their conduct under fire.

“To say that our police officers put their life on the line every day is no hyperbole, ladies and gentlemen,” Rawlings said.

“Leadership matters at this time – I’m proud of our chief,” he added.

For more on this story, see President Obama’s remarks on the Dallas police shooting, how Texas officials are reacting, and why Ross Ramsey says we should “save the hashtags for later” after Dallas attacks.