Dallas police officers shot dead: What we know so far
Five police officers have been shot and killed during a protest in Dallas over the deaths of two black men at the hands of white officers earlier this week.
Here's what we know so far:
What has happened?
At least two snipers opened fire on officers from what has been called an ambush-style "elevated position" during protests in Dallas on Thursday night.
A total of 12 officers were shot, five of whom have died. Two civilians have also been injured.
Three people are in custody.
Why?
Police do not yet know the motive of the shooters.
Police chief David Brown said the suspects caught have not been talking.
"We just are not getting the cooperation we'd like to know that answer of why, the motivation, who they are," he said.
Who has been arrested?
Three suspects are in custody, though we don't know their identity yet.
One suspect was engaged in a shootout with SWAT officers before he was arrested. A suspicious package was discovered nearby but was secured by a bomb squad.
A second suspect handed himself in, after Dallas Police released a photo of him on Twitter as a "person of interest", and a woman became the third to be arrested.
Are there any other suspects?
A fourth suspect was killed after being cornered on the second floor of a nearby building.
Police tried to negotiate with the man for "several hours", but talks broke down and there was an exchange of gunfire.
Dallas Police Chief, David Brown, said his force "saw no other option but to use our bomb robot, and place a devise on its extension for it to detonate where the suspect was. Other options would have exposed our officers to grave danger."
Before he was killed, the suspect told the negotiator that he was "upset about the recent police shootings, upset at white people and that he wanted to kill white people - especially officers."
The suspect said he was not affiliated with any groups, and he acted alone.
Earlier on Thursday, the suspect had threatened to "hurt and kill" as many officers as possible.
He told police "the end is coming", and claimed there were bombs "all over the place", both in the garage and in downtown Dallas - however none were found after sweeps by bomb disposal experts.
Police are working on the assumption that the shooters were working together in a coordinated attack.
Mr Brown said investigators do not know whether more people were involved or not.
Who was shot?
Only one of the officers killed has been identified so far.
Brent Thompson, aged 43, had been a member of the Dallas Area Rapid Transit (DART) force since 2009.
The other four victims, all from Dallas Police Department, have not yet been named.
Four other police officers and three other DART officers were also shot and injured.
What were the protests about?
Protests have been taking across the United States after the fatal killing of two black men by white officers in two separate incidents.
Alton Sterling, 37, was pinned to the ground and shot in the chest in Baton Rouge, Louisiana on Tuesday. The shooting was caught on camera.
Philando Castile, 34, was shot dead by officers during a traffic stop in Minnesota a day later.
Castile's girlfriend streamed the aftermath of the shooting on Facebook
The police officer who fatally shot him has been named by state investigators as Jeronimo Yanez, who opened fire "multiple times".
Fellow officer Joseph Kauser was also involved.
The names of the officers involved in the shooting of Alton Sterling have yet to be revealed.