Five police officers were fatally shot and seven others wounded Thursday when snipers opened fire in downtown Dallas during a protest over recent police shootings in Minnesota and Louisiana, police said.
Here is what we know so far:
Homeland Security Secretary Jeh Johnson said "there appears to have been one gunman" in the shooting.
Investigators discovered bomb-making materials, rifles and a “personal journal of combat tactics” in the shooter's home.
Police cornered one suspect and tried to negotiate with him for several hours but “negotiations broke down” and turned into “an exchange of gunfire with the suspect.”
A "bomb robot" was used to kill the gunman, identified as Micah X. Johnson, 25, a resident of the Dallas area.
Other suspects are in custody, but officials declined to say how many.
In addition to police officers, two civilians -- a man and a woman -- were shot and injured
President Obama will cut short his trip to Europe and visit Dallas next week at the invitation of the mayor, the White House said Friday. Obama canceled a sightseeing jaunt to Seville, Spain, that was tacked on to his trip to Poland for the NATO summit. Obama will instead fly from Warsaw to Madrid on Saturday night and meet with Spanish officials, then return to Washington on Sunday night, a day earlier than planned.
Obama will visit Dallas early next week, Press Secretary Josh Earnest said. He gave no further details.
Dallas Mayor Mike Rawlings said Friday that he believed the gunman who attacked police Thursday night was a lone shooter.
Rawlings said Micah Xavier Johnson, 25, was “the lone gunman in this incident.”
“This was a mobile shooter that had written manifestos on how to shoot and move,” Rawlings said. “He did that. He did his damage. But we did our damage to him, too.”
Jul. 8, 2016, 3:27 p.m.
This was a man we gave plenty of options to, to give himself up peacefully, and we spent a lot of time talking. He had a choice to come out and we would not harm him, or stay in and we would. He picked the latter.
Dallas Mayor Mike Rawlings
Jul. 8, 2016, 3:23 p.m.
Remember this: We know what the mayor said about the gunman. What we don’t know is who, if anybody, may have known what the gunman knew, what he was going to do, may have assisted him in any of his efforts.
At a press conference Friday afternoon, Homeland Security Secretary Jeh Johnson said that "there appears to have been one gunman" in the Dallas shootings.
The gunman, Micah Xavier Johnson, 25, had "no known links to or inspiration from any international terrorist organization," Johnson told reporters.
The shooter acted with "a depraved misbelief that the murder of police officers solves a problem," he said.
Just as the gunman does not represent those who protest for change, police officers who use excessive force do not represent all of law enforcement, the secretary added.
"Violence is never the answer. Violence directed at our police officers is never the answer. Violence directed at police officers endangers them, and it endangers the very public they are sworn to protect," he said.
Dallas gunman Micah Xavier Johnson "bantered" with police negotiators, a federal official said. Johnson did not appear nervous, indicated he was not afraid to die in a hail of gunfire and told officers he had been preparing for the assault.
As Americans coped with one tragic moment after another this week, with the deaths of Alton Sterling and Philando Castile followed by the shooting of a dozen police officers in Dallas, the country’s parents had an added task: explaining each act of violence to their children.
“If [children] see a bunch of this on television, they can become the indirect victims of trauma,” said Suzanne Silverstein, director of the Cedars-Sinai Psychological Trauma Center.
African American children might be afraid for their own lives or for their friends and families when they see black men being shot. Children of law enforcement officers might be even more afraid for their parents after learning what happened in Dallas.
White House aides did not rule out the possibility Friday that the Dallas shooting may cut short President Obama’s trip to Europe, where he was receiving regular updates on the investigation as he shuttled between NATO summit meetings in Warsaw.
Obama feels "not just a need but a desire to communicate with the American public about his perspective on these issues,” White House Press Secretary Josh Earnest said of the racially tinged violence that has roiled the nation over the past three days.
Americans’ heightened concerns about safety are understandable after the Dallas massacre and two shooting deaths of black men by white police officers in Louisiana and Minnesota, particularly given how the advent of social media and readily available recording technology relay those episodes more directly and immediately, Earnest said.