The gunman who killed five police officers and wounded nine other people in Dallas this week had been accused of "egregious" sexual harassment in the Army and spent years accumulating a stockpile of weapons, according to investigators and his military lawyer.
The new details about Micah Xavier Johnson, 25, emerged Saturday as Dallas grieved and police remained on edge following the nation's deadliest attack for law enforcement officers since Sept. 11, 2001.
Mourning at a memorial site outside the downtown police headquarters was interrupted in the afternoon by a report of a suspicious person in a parking garage behind the headquarters.
About a dozen officers could be seen rushing into the structure as police cruisers and a SWAT vehicle arrived as reinforcements. The police used explosives and a shotgun to breach locked fences and doors but did not find any suspects.
Johnson was killed by a police robot carrying a pound of C-4 explosives in a claw arm after he ambushed officers at a demonstration Thursday protesting recent high-profile police shootings, police said.
Investigators believe that he had assembled an arsenal of bomb-making materials, five handguns and a semi-automatic SKS assault rifle within the last two years, according to a federal law enforcement official who was not authorized to speak publicly about the case. The first three handguns were purchased in September 2014, the officer said.
Officials have said that Johnson, who was black, kept a personal journal filled with combat tactics and wanted to kill white police officers following recent high-profile police shootings of black men.
Dallas County Judge Clay Jenkins, the county's chief executive, said the journal shows that Johnson had "a detailed plan" and that it "wasn't a journal of incoherent ramblings."
Neighbors saw him doing military exercises in his backyard in the weeks before the attack, said Jenkins, adding that Johnson told a police negotiator he had been practicing for months.
Johnson also took a "simulated handgun" class at the Academy of Combative Warrior Arts in the Dallas suburb of Richardson about two years ago, according to an employee.
"Micah just took basic self-defense with us. We don't know anything about him," said Justin Everman, the school's owner.
President Obama on Saturday called Johnson a "demented individual" who did not represent the feelings of other Americans.
Investigators were digging into Johnson's military history and are seeking to corroborate reports that he was sent home from Afghanistan after a woman lodged a complaint of sexual harassment against him in 2014, another federal law enforcement official said.
Bradford Glendening, the lawyer who represented Johnson, told the Associated Press that the military recommended an "other than honorable discharge," adding, "In his case, it was apparently so egregious, it was not just the act itself.… I'm sure that this guy was the black sheep of his unit."
According to a court filing Glendening read to the AP, the victim said she wanted Johnson to "receive mental help" and sought a protective order to keep him away from her and her family. Johnson was ordered to avoid all contact with her, Glendening said.
The Army said it was not authorized to comment on any administrative action taken against Johnson.
Johnson joined the Army Reserve in March 2009 and served in a unit based in Seagoville, Texas, for 4 1/2 years. He deployed to Afghanistan with the 420th Engineer Brigade in 2013 and served eight months there as a carpentry and masonry specialist���.
Johnson's former high school classmates were bewildered by his transformation from an easygoing junior ROTC member into a solemn aficionado of radical black separatist movements, said Patricia Phillips, 26, of Mesquite, Texas.
"That's not the guy that I knew in high school.… He was just generally funny," said Phillips, adding that Johnson didn't seem to care about her race. "He hung out with all kinds of kids."
Phillips said fellow graduates of the class of 2009 at John Horn High School were "just kind of flabbergasted, you know, just knowing that we walked the halls with him and talked to him and had classes with him and knew this completely different guy than what happened and what we saw on Thursday."
Investigators were still examining whether others might have been involved in Thursday's attack, said Texas Atty. Gen. Ken Paxton, who stopped by the memorial Saturday.
"We know there is only one shooter but we're not sure if there were conspiracies involved," Paxton said.
Mourners placed bouquets, cards, candles and other tributes on top of two cars parked in front of the building's entrance, one belonging to the department, the other from Dallas Area Rapid Transit.
DART Officer Brent Thompson, 43, who had worked for the department since 2009, was among those killed. He was the department's first officer to be killed in the line of duty.
A fellow officer said Thompson was quiet and determined, and was working to transfer to the department's motorcycle division.
Among those paying tribute to Thompson on Saturday was fifth-grader Victor Becerra, who didn't know him by name. Victor just called him his police officer friend.
The 10-year-old met Thompson after having emergency surgery for appendicitis. Thompson stopped by his hospital room to say hello and make him laugh.
At one point, Victor — who wants to be a police officer — confided in Thompson, "I'm afraid of dying."
"No," Thompson told him. "God is with you."
When Victor spotted two soldiers standing at attention at the memorial Saturday, he joined them and saluted too.
The four Dallas police officers killed included Patrick Zamarripa, a 32-year-old father and Navy veteran who enlisted as a teenager just before the Sept. 11 attacks.
Zamarripa survived three tours in Iraq, where he worked as a military policeman, and saw the downtown Dallas police beat as good training for future assignments, according to his father, Rick, who drove to the headquarters Saturday to see the memorial and where his son died.
Policing "was always his passion," said Rick Zamarripa, 61. "He was patient, helpful. He was always very giving. He gave his life to protect people. And he paid the ultimate price."
Zamarripa would like to see a permanent monument erected to honor the sacrifices made by his son and other officers.
"Patrick was a humble, passionate, giving person. He was a hero," his father said. "The city of Dallas should have a memorial for all the five fallen officers and all the other fallen officers."
The names of the other victims had not been officially released Saturday, but local media identified them as Senior Cpl. Lorne Ahrens, 48, a former Los Angeles County sheriff's dispatcher; Officer Michael Krol, 40; and Sgt. Michael J. Smith, 55.
Seven other officers were injured in the shooting, some of whom were still hospitalized Saturday.
DART officers Omar Cannon, 44, and Misty McBride, 32, were still recovering but "doing well," said fellow Officer Terry Mack as he paid his respects at the DART police car.
Charissa Williams, 41, drove overnight from Baton Rouge, La., to pay her respects. She placed balloons and flowers at the memorial. Although she supports aspects of the Black Lives Matter movement, Williams, who is black, said, "Not all officers are bad officers."
"I'm not against police officers; I'm against wrong," she said, including the recent police shootings of Alton Sterling in Baton Rouge and Philando Castile in Falcon Heights, Minn.
She noted that the Dallas protest "was a peaceful march, and one individual just came in and turned it into a catastrophe."
Dallas Mayor Mike Rawlings also stopped by the memorial before entering police headquarters Saturday. He urged the city to overcome its racial divisions.
"It's all about race," Rawlings said. "Let's get over it, build a bridge and get over it."
Times staff writers Nigel Duara in Dallas and W.J. Hennigan in Washington contributed to this report.
9:44 p.m: This article was updated with new details.
7:53 p.m: This article was updated with additional details about the shooter.
6:38 p.m.: This article was updated throughout with additional details about the shooter and the victims.
4:54 p.m.: This article was updated with additional details about Johnson's weapons purchases.
4:41 p.m.: This article was updated with an unspecified threat at the Dallas police headquarters
4:09 p.m.: This article was updated with additional details from the memorial site.