A Dallas police officer, who did not want to be identified, takes a moment as she guards an intersection in the early morning after a shooting in downtown Dallas on Friday. (LM Otero/AP)

Three nights, three shootings, seven deaths.

After multiple snipers opened fire on law enforcement in Dallas on Thursday night, killing five uniformed officers and injuring six others, after three days of outrage over police-involved shootings and not even a month since the tragic Orlando massacre, a sorrowful nation was left asking: What next?

“Vicious, calculated” and a “despicable attack” is how President Obama described the ambush.

“I believe I speak for every single American,” Obama said from an early morning news conference in Poland, “when I say we are horrified over these events.”

It was the second time Obama had somberly addressed the nation in less than 24 hours.

The week began July 4, a day doused in stars and stripes for a nation collectively celebrating its founding and fundamental principles: freedom, liberty, justice for all. After a string of terrorists attacks worldwide, authorities remained vigilant. But the day passed without national tragedy.

Then came Tuesday, when not even an hour after Independence Day turned to July 5, cellphone cameras captured video of a white Baton Rouge police officer fatally shooting a black man named Alton Sterling outside a convenience store where he was selling CDs. On national television the next day, his 15-year-old son uncontrollably sobbed.

Less than 48 hours later, in the week’s second controversial gun death, a Minnesota police officer shot a school cook multiple times during a traffic stop after the man, also black and named Philando Castile, said he was carrying a concealed weapon and allegedly reached for his wallet. His girlfriend, sitting in the passenger seat as he bled out beside her, live-streamed the aftermath on social media. At the end of the video, as the sobbing woman sits with her 4-year-old daughter in the back of a police cruiser, the little girl tried to offer some comfort.

“It’s okay, Mommy,” she said. “It’s okay. I’m right here with you.”

Protests of the Black Lives Matter movement erupted across the country, their tone and message not unlike those that followed the deaths of other black men at the hands of police since 2012.

On Thursday night, one such demonstration took over downtown Dallas, a rally 800-people strong and monitored by throngs of police. Marchers chanted “no justice, no peace” and “hands up, don’t shoot.”

Then, gunfire rang out.

And just like the shootings that had inspired the demonstration in the first place, portions of this atrocity were also captured on video, the horror of it all unfolding intimately, and live, on Facebook, Periscope, Twitter and Instagram.

Video footage from witnesses shows police officers taking cover behind cruisers, red and blue lights swirling. The sound of rapid gunfire meshed with screams and sirens. In each, one phrase is continually repeated: “Oh, my God.”

Most chilling was a clip of what appears to be a gunman, armed with some type of semi-automatic rifle, swiftly maneuvering between building pillars on a downtown Dallas sidewalk before cornering an officer and shooting him.

And in a world so defined by how tragedy unfolds online, new hashtags defining this week emerged:

#AltonSterling

#PhilandoCastile

#Dallas

#PrayForAmerica

“Tonight’s assassinations undermine our democracy and were an attack on us all,” Los Angeles Mayor Eric Garcetti tweeted early Friday. “We cannot let hate spread like a disease in our country.”

A host of other protests occurred across the country Thursday night, including in New York City, Washington, Philadelphia, Oakland and Atlanta.

At a protest in Portland, a man toting camera gear struck fear in protesters when he pulled a handgun and aimed it at the crowd, reported the Oregonian. He was later arrested and charged with disorderly conduct, according to the newspaper, and told a reporter he runs LaughingAtLiberals, a YouTube channel dedicated to “exposing the lunacy of the left.” The paper could not confirm that information.

Protesters in Oakland waded into traffic on a busy interstate, and a photo posted to social media showed someone had defaced the Oakland Police administration building with sexually explicit graffiti.

In New York City, police told NBC New York that at least 40 people were arrested during protests that were mostly peaceful but occasionally sparked clashes with authorities.

Across social media, people going to sleep as the sniper attacks unfolded in Dallas and those waking up to news of multiple deaths expressed outrage and overwhelming sadness.

This week’s violence comes less than a month after a gunman, armed with an assault rifle, fatally shot 49 people at an Orlando gay nightclub in early June and injured even more. It was the most deadly mass shooting in U.S. history, and an attack that rattled, then united, the nation’s LGBT community.

It also reignited an ongoing, contentious debate over gun control in America, rallying the voices of family members and victims of past mass shootings.

Guns, though not the focus, were mentioned in Obama’s early morning address from Poland on Friday.

“We also know when people are armed with powerful weapons, unfortunately it makes attacks like these more deadly and more tragic,” Obama said. “And in the days ahead we are going to have to consider those realities as well.”

The president said the FBI is already working with Dallas police on the investigation and said he will make further statements as more facts are uncovered. He condemned all violence against law enforcement, and said there is “no possible justification for these kinds of attacks.”

“Justice will be done,” he said.

On Thursday, before tragedy overtook Dallas, Obama called on all Americans to refrain from dismissing police-involved shootings disproportionately affecting people of color, but he also expressed his support for men and women in law enforcement. He echoed that sentiment early Friday.

“I also said yesterday that our police have an extraordinarily difficult job, and most of them do their job in outstanding fashion,” Obama said. “Today is a wrenching reminder of the sacrifices they make for us.”

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