An Army veteran “upset about Black Lives Matter” and “recent police shootings” who opened fire Thursday night in Dallas in an attack on police officers has been identified as Micah Xavier Johnson, the Los Angeles Times and CBS News report.

Five police officers were killed and seven were wounded, officials said. Two civilians were also wounded in the shootings. Johnson, 25, was killed when a police robot detonated a bomb near him following a standoff that lasted several hours, Police Chief David Brown said Friday at a press conference.

“The suspect said he was upset with white people and wanted to kill white people, especially white officers,” Brown said.

It is not clear if there were any other gunmen, or whether other people taken into custody by police were involved in the shooting. Police initially said two snipers positioned themselves in triangulated locations to fire on officers from elevated positions.

The gunfire began just before 9 p.m. while a peaceful rally was held by the Black Lives Matter organization in response to recent controversial police killings of black men in Louisiana and Minnesota. The officers were fired upon by a gunman with a sniper rifle in an elevated position at times during the incident, officials said.

The gunman was then cornered in El Centro College in downtown Dallas.

Little is known about the gunman so far, and this post will be updated as more information is released. Here’s what we know so far about the suspected shooter and the tragic incident:

The Former Soldier Told Police He Was Not Affiliated With Any Groups & He ‘Did This Alone’

After the shootings in downtown Dallas, the gunman, identified as Micah Xavier Johnson, 25, holed himself up inside the El Centro College building in the downtown area of the city, Dallas Police Chief David Brown said at a press conference.

He told police he was “not affiliated with any groups,” and he said he “did this alone,” the chief said.

Sources told the Los Angeles Times that Johnson has no ties to terror groups and no known criminal history. He has lived in the Dallas area and has family members living in Mesquite, Texas, east of Dallas, the newspaper reports, citing federal law enforcement sources.

A black SUV was found at the scene registered to Delphene Johnson, who is Micah Johnson’s mother according to Facebook posts and public records, NBC Dallas-Fort Worth reports. Live helicopter video from the news station showed police at her home in Mesquite.

Johnson served in the U.S. Army Reserve, investigators said.

Johnson told police negotiators the “end is coming” and said he wanted to “kill more” officers, according to Brown.

Police said after several hours of negotiating and shooting at the officers, the suspect was killed by a bomb-wielding robot.

“We tried to negotiate for several hours, negotiations broke down, we had an exchange of gunfire with the suspect,” Brown said. “We saw no other option but to use our bomb-robot and place a device on its extension for it to detonate where the suspect was. Other options would have exposed our officers to grave danger. The suspect is a result of detonating the bomb.”

The suspect did not shoot himself, despite reports, Brown said.

“He wanted to kill officers, and he expressed killing white people, he expressed killing white officers,” Brown said. “He expressed anger for Black Lives Matter. None of that makes sense, none of that is a legitimate reason to do harm to anyone, so the rest of it would just be speculating on what his motivations were. We just know what he said to our negotiators.”

While he was barricaded in the hotel, the suspect told police there were bombs planted “all over” downtown Dallas, the city’s police chief said at a press conference.

Police have not said if any bombs or suspicious items have been found.

“He said we will eventually find the IEDs,” Police Chief David Brown said at a press conference.

The shooting came a year and a month after a man angry at police opened fire on the Dallas Police headquarters. He fired several shots at the building, but no one was injured. The man,J ames Boulware, was driving an armored van and was later chased down by police. He was killed during a standoff.

Boulware also claimed he had planted bombs in downtown Dallas.

Dallas Police Headquarters Shooting: 5 Fast Facts You Need to Know

An armored vehicle shot at officers and the Dallas Police headquarters early Saturday morning before leading police on a chase and into a standoff.

 

His Facebook Page Includes a ‘Black Power’ Poster

Micah Johnson’s Facebook page provides few details about his life. In May, he posted a “Black Power” poster, one of the few images on his page:

His cover photo is the Pan-African flag.

Johnson posted a photo with Professor Griff of Public Enemy, taken at what appears to be an autograph signing, in April. His only other photo is a Doctor Who wallpaper.

His birthday was July 2.

Johnson’s sister posted on Facebook on Friday after his name was made public, “I keep saying its not true…my eyes hurt from crying. Y him??? And why was he downtown smh.”

Officer Brent Thompson: 5 Fast Facts You Need to Know

Officer Brent Thompson, the first slain officer shot in Dallas identified, had trained Iraqi and Afghan police. He was 43, and a DART officer.

Police Are Still Searching Until they Determine There Are No Outstanding Suspects, the Chief Said

Police are still trying to determine how many gunmen were involved in the attack. Chief David Brown said they will continuing searching and investigating until they can be sure no one is on the loose.

Brown said they want to ensure “that everyone associated with this tragic is brought to justice. … We won’t expand on any further on what other suspects we have interviewed or looked at or their status until we get further into this investigation and get closer to a conclusion of who are all involved.”

Brown said, “I’m not going to be satisfied until we turn over every stone. … We’re not satisfied that we’ve exhausted every lead. And we’re not going to be satisfied until every lead is exhausted. So if there is someone out there that was associated with this, we will find you and we will prosecute you and we will bring you to justice.”

Police previously said two people were spotted getting into a Mercedes into downtown Dallas carrying camouflage duffle bags, the police chief said. The car was spotted by police and stopped on the highway. The people in the car were taken into custody. The chief said a woman was also arrested near El Centro College.

Police are not sure if any of those three people who are in custody are connected to the shooting.

One man who was marching during the protest, Mark Hughes, was incorrectly identified by police as a “person of interest” in the shooting, and his photo was distributed on Twitter by the department. Hughes was open carrying a rifle, which is legal in Texas, to exercise his Second Amendment rights, but he turned over the gun to a police officer after the shooting began so he would not be mistaken as a suspect. That moment was caught on video:

The man later turned himself in to police after his photo was distributed across social media and on national television. He was released after being questioned.