DALLAS — Micah Xavier Johnson was known by his family and neighbors as an “Army strong” veteran who served in Afghanistan and loved playground basketball back home in suburban Dallas.

He’s now known more widely as the 25-year-old armed suspect killed Friday just hours after five police officers were fatally shot and seven wounded after a downtown demonstration.

Johnson was believed to have shared a two-story tan brick home in Mesquite, about 30 minutes east of Dallas, with family members. He graduated from John Horn High School in Mesquite, school district officials said.

He began serving the Army in March 2009, Army officials said. Johnson was a private first class with a military occupational specialty of carpentry and masonry. Toward the end of his tenure, Johnson was deployed to Afghanistan from November 2013 and returned in July 2014. His service ended in April 2015.

On what appears to be Johnson’s Facebook page, photographs posted by someone who identified herself as a relative showed him in a U.S. Army uniform and holding an unknown object as though it were a weapon.

The relative also left a comment on his birthday in 2014 that called him “definitely Army strong” and an “entertaining, loving, understanding, not to mention handsome friend, brother (and) son.”

The shootings began shortly before 9 p.m. Thursday when, police say, an uncertain number of snipers shot and killed five police officers, wounded seven more and injured two civilians. A demonstration to protest the recent killings of black men by police in Baton Rouge, Louisiana, and St. Paul, Minnesota, was wrapping up when gunfire erupted, police said.

Hours later, police cornered Johnson in a parking garage and began lengthy negotiations. After those failed, police used explosives delivered by a robot to “blast him out” and he died, said Dallas Mayor Mike Rawlings in a Friday morning news conference.

During those waning moments of Johnson’s life, police say, he had told negotiators he was upset about recent police shootings and wanted to kill white people, particularly white officers.

Dallas Police Chief David O. Brown added in a news conference Friday that the suspect said he’d acted alone and was unaffiliated with any group, though it remains unclear whether that was the case. Brown said there were others in custody but he would not discuss the nature of those detentions. The chief added that police still didn’t know if investigators had accounted for all participants in the attack.

After Johnson was killed, a relative posted onto her Facebook page, “I keep saying its not true…my eyes hurt from crying. Y him??? And why was he downtown.” She did not respond to Facebook messages.

For several hours Friday morning, police blocked access to the home where Johnson was believed to have lived in Mesquite, a blue-collar suburb. Investigators in Bureau of Alcohol, Tobacco, Firearms and Explosives vests were seen carrying out several bags of material.

Just before noon Friday, officers stopped blocking the street in Mesquite. After that, no one answered a knock on the door.

Nearby, Israel Cooper said Johnson went by the name Xavier. Cooper says Johnson had a “cool vibe” and wasn’t really political but did seem educated.

He says he played basketball with him at a park near the house. He says, “He would be out there for eight hours. Like it was his job. Just hoopin’.”

Cooper said that when he heard the suspect was Johnson, he “was in disbelief because he’s just not like a violent or rough dude.”

“So I was, ‘nah, it’s probably another Xavier somewhere, you know,’ ” Cooper said. “But then, with pictures on the internet and stuff, I’m like ‘OK.’ ”

Cooper added: “It’s the quiet ones that just do the most devastating stuff. You never see it coming. But then it’s more expected, like ‘I should have known.'”