A peaceful protest in Dallas over the recent videotaped shootings of black men by police turned violent Thursday night as an unknown number of people shot at officers, killing five and injuring seven, as well as two civilians. Here's what is known about the deadliest day for U.S. law enforcement since 9/11:
Hundreds gathered in downtown Dallas to protest the deaths of Alton Sterling in Baton Rouge, Louisiana, and Philando Castile in suburban St. Paul, Minnesota. About 8:45 p.m. Thursday, shots were fired by snipers, authorities have said. The shootings happened a few blocks from Dealey Plaza, the landmark made famous by President John F. Kennedy's assassination.
HOW MANY WERE INVOLVED IN THE SHOOTINGS
Authorities initially said that there were three suspects in custody and a fourth one that was killed by a robot-delivered bomb in a parking garage after a long standoff, but by Friday morning, officials were vague and would not discuss details of the situation.
Authorities have identified the man who died as 25-year-old Micah Johnson, a black man who lived in the Dallas suburb of Mesquite. He had served from March 2009 to April 2015 in the Army Reserve and did one tour of duty in Afghanistan.
Police searched Johnson's home and found bomb-making materials, ballistic vests, rifles, ammunition and a personal journal of combat techniques.
Johnson told authorities that he was upset about the recent shootings of black men by police and wanted to kill whites, "especially white officers," according to Dallas Police Chief David Brown. Johnson also told them that he worked alone, though authorities have not confirmed that.
Five Dallas police officers were killed in the shootings. The names, service times and details about all of them have not been released. Law enforcement officials did not immediately disclose the race of the officers, either.
One of them, Officer Brent Thompson, was described as "courageous" and a newlywed, according to Dallas Area Rapid Transit police Chief James Spiller.
Seven officers were injured in the shootings. Dallas Mayor Mike Rawlings said one of the wounded officers had a bullet go through his leg as three members of his squad were fatally shot around him.
"We care so much about people protesting, and I think it's their rights. But how we handle it can do a lot of things," Rawlings said. "One of the things it can do is put our police officers in harm's way, and we have to be very careful about doing that."
Among the two civilians injured was Shetamia Taylor, 37, who was shot in the right calf, according to sister Theresa Williams. Taylor threw herself over her four sons, ages 12 to 17, when the shooting began.
Witnesses said the scene was chaotic, with protesters scattering when the shots rang out and officers crouching beside vehicles.
Texas Gov. Greg Abbott directed the Texas Department of Public Safety to offer "whatever assistance the City of Dallas needs" and emphasized "the importance of uniting as Americans."
President Barack Obama called the shootings "vicious, calculated and despicable."