LM Otero / AP

Updated July 8 at 4:06 p.m.

Within a 24-hour span, President Obama delivered remarks twice about shooting incidents in the United States—the first on the officer-involved shooting deaths in Louisiana and Minnesota, and the second on an attack against law-enforcement personnel in Dallas.

In Dallas, five police officers were killed by snipers, after protesters gathered in the wake of the shooting deaths of Alton Sterling in Louisiana and Philando Castile in Minnesota. Several other officers were injured in the attack.

“We are horrified over these events, and that we stand united with the people and the police department as it deals with this tremendous tragedy,” Obama said on Friday. “We still don’t know all the facts. What we do know is that there has been a vicious, calculated, and despicable attack on law enforcement.” Obama ordered Friday that American flags at the White House and at federal, embassy, and military buildings be flown at half-staff.

In a press conference Friday afternoon, Attorney General Loretta Lynch said officials from her department—including from the FBI—are on the ground in Dallas to help local and state officials. She did not indicate whether the Justice Department is planning to launch a formal investigation.

Lynch, as other officials have, called for calm in the wake of this week’s tragedies: Thursday night’s events in Dallas and the two police-involved shootings in Louisiana and Minnesota. Her department is already involved in investigating the latter incidents. It opened a criminal probe into the circumstances surrounding the death of Sterling, who was shot and killed by police in Baton Rouge on Tuesday; and it’s keeping tabs on a local law-enforcement investigation into the death of Castile in the St. Paul area on Wednesday. Hours after Castile was killed by police during a traffic stop, Minnesota Governor Mark Dayton called for a full-fledged Justice Department investigation in his state.

In her remarks, Lynch acknowledged that many Americans are feeling a “sense of helplessness, of uncertainty, and of fear,” but mustn’t respond with violence. “Rather, the answer must be action: calm, peaceful, collaborative and determined action,” Lynch said. “We must continue working to build trust between communities and law enforcement. We must continue working to guarantee every person in this country equal justice under the law. We must take a hard look at the ease with which wrongdoers can get their hands on deadly weapons and the frequency with which they use them. We must reflect on the kind of country we want to build and the kind of society we want to pass on to our children.”

On Friday afternoon, Texas Governor Greg Abbott also reacted to the shooting in Dallas, saying in an open letter:

In the coming days, there will be those who foment distrust and fan the flames of dissension.

To come together - that would be the greatest rebuke to those who seek to tear us apart.

There is far more that binds us together. We see that great strength in times of tragedy, in times of great need. Whether fire or flood or the acts of depraved individuals, Texans are the first to open their hearts, their homes, their wallets to offer charity and love.

I ask for your prayers - for our law enforcement officers, for the city of Dallas, for our state and for our nation.

Texas Lieutenant Governor Dan Patrick told FOX News, “I do blame people on social media with their hatred toward police. I do blame…[people] calling police racist without any facts. I do blame former Black Lives Matter protests. Last night was peaceful, but others have not been… this has to stop.”   

In the afternoon, former House Speaker Newt Gingrich, appearing live with Vann Jones on Facebook, saidIt's more dangerous to be black in America. ... I think sometimes for whites it's difficult to appreciate how real that is.” But Gingrich, who’s reportedly being considered as Donald Trump’s running mate, has a history of “racial insensitivity.”

On the campaign trail, Hillary Clinton and Trump canceled events. Clinton’s campaign postponed an event with Joe Biden in Pennsylvania “due to the tragic events in Dallas.” In a tweet, she said:

In an interview with CNN's Wolf Blitzer on Friday afternoon, Clinton called police officers' actions ahead of the Dallas shootings—protecting peaceful protesters—a "hallmark of America," and said steps must be taken to protect police and citizens alike. She specifically called for national guidelines for officers' use of force and an examination of their implicit biases against minorities—two elements of her criminal-justice platform. "We just have to make up our minds that we are going to bring our country together," Clinton said. "This is much deeper even than these terrible killings. We have got to start, once again, respecting and treating each other with the dignity that every person deserves."

Donald Trump, who was scheduled to campaign in  Florida, issued a statement, saying the shootings were “a coordinated, premeditated assault on the men and women who keep us safe.” He continued:

We must restore law and order. We must restore the confidence of our people to be safe and secure in their homes and on the street.

The senseless, tragic deaths of two motorists in Louisiana and Minnesota reminds us how much more needs to be done.

This morning I offer my thoughts and prayers for all of the victims’ families, and we pray for our brave police officers and first responders who risk their lives to protect us every single day.

Our nation has become too divided. Too many Americans feel like they’ve lost hope. Crime is harming too many citizens. Racial tensions have gotten worse, not better. This isn’t the American Dream we all want for our children.

This is a time, perhaps more than ever, for strong leadership, love and compassion. We will pull through these tragedies.

Bernie Sanders said on Twitter Friday, “If there is a police related shooting, that should trigger an immediate investigation with the Department of Justice.” Later adding:

Obama addressed the Louisiana and Minnesota shootings on Thursday. “When incidents like these occur, there’s a big chunk of our fellow citizens that feels as if because of the color of their skin, they are not being treated the same—and that hurts,” he said, after arriving in Warsaw for the NATO summit. “And that should trouble all of us. This is not just a black issue. It’s not just a Hispanic issue. This is an American issue that we should all care about.”

A flurry of responses to Dallas came in over night from lawmakers. Representative Pete Sessions of Texas, who has an office in Dallas, said in a statement Thursday. “Tonight I join the people of Dallas, Texas, in praying for the safety of the Dallas Police Officers and all who are in the downtown are this evening. Our police officers selflessly put their lives on the line every single day to vigilantly protect our families and communities and it is devastating to think that someone deliberately targeted our law enforcement.”

Dallas-area Representative Marc Veasey, a Democrat, commended the bravery of the Dallas and DART police departments in a statement. “This appears to be a vicious and calculated attack on our law enforcement community, but we must remember that violence of any kind does not solve violence against another community,” he said. “The loss of one life to gun violence should be treated as a tragedy. The people of Dallas need to remain united and assist our local police department by providing any information they have about last night’s shooting.”

Republican Representative Jeb Hensarling, of Texas, said,This tragedy literally hits close to home.  This act of evil and cowardice took place just a few miles away from where my family goes to sleep every night—a place I’ve called home for more than 30 years. This tragic event reminds us that so much of our safety depends on that thin blue line—those that put their lives on the line for us each and every day.”

Former President George W. Bush, who lives in Texas, said in a statement: “Laura and I are heartbroken by the heinous acts of violence in our city last night. Murdering the innocent is always evil, never more so than when the lives taken belong to those who protect our families and communities.”

Texas Senator Ted Cruz also expressed his condolences, tweeting:

Senate Minority Leader Harry Reid also responded to the attack on Twitter:

House Speaker Paul Ryan, whose chamber has been embroiled in a debate over gun-control legislation in recent weeks, said Friday morning that “no one else” but “a few perpetrators of evil” are to be blamed for the Dallas shooting. He went on:

As the president rightfully said, justice will be done. We also have to let the healing be done as well. This has been a long week for our country. It's been a long month for America. We've seen terrible, terrible, senseless things. Every member of this body, every Republican and every Democrat, wants to see less gun violence. Every member of this body wants a world in which people feel safe regardless of the color of their skin. And that's not how people are feeling these days. Sometimes we disagree on how to get there. Sometimes we disagree passionately on how to get there. But in having this debate, let's not lose sight of the values that unite us. Let's not lose sight in our common humanity.

Minority Leader Nancy Pelosi followed Ryan’s remarks. “The ambush and murder of police officers during a peaceful protest is a tragedy that tears at the heart of every American,” she said. "I agree with the speaker that episodes like this must not harden our divisions, but should unify us as a country. We are all horrified by this despicable act of violence, and we share in the shock and grief for the officers killed, their loved ones and the entire Dallas community.”

Chairman of the Congressional Black Caucus G.K. Butterfield, flanked by caucus members, vented frustrations with Republicans, calling for legislative action on guns during a news conference Friday morning. “America is weeping. They are angry. They are frustrated. And Congress, when I say Congress, I mean the Republicans in Congress, are refusing to address gun violence in America that targets black men and black women, and Hispanic men and Hispanic women, and yes, even police officers,” Butterfield said.

Representative John Lewis, who led the House sit-in last month, was among those in attendance. Lewis, who was also an activist in the Civil Rights Movement, said “The scars and stains of racism are still deeply embedded in America society...We have to deal with it.” He added: “[I was] left bloody, unconscious by police officers, but I never hated… I said ‘Thank you for your service.’”

Some Republicans have criticized Obama’s comments, including his statement that “when people are armed with powerful weapons, it makes attacks like these more deadly and more tragic.” Among them, former presidential candidate Ben Carson: “Now is definitely not the time to get political,” he told Fox and Friends. “Now is the time to use logic and ask ourselves, why do we have a Constitution? Why do we have a Second Amendment? They’re always saying you don't need a high powered weapon to hunt deer. The Constitution is not about deer hunting. It's about people being able to defend themselves from an overly aggressive government or an external invasion.”

Former Arkansas Mike Huckabee told Fox News Obama “doesn’t need to inject the divisive arguments like gun control at a time of great grief for the nation. And he ought to do for us what Ronald Reagan did after the Challenger disaster.”

This post will be updated as responses continue to come in.

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