The nation is reeling one day after the deadliest school shooting in modern Texas history, and authorities on Wednesday provided more information about the gunman whose massacre killed 19 children and two teachers at an elementary school in Uvalde, Texas.
Texas Gov. Greg Abbott identified the assailant as Salvador Ramos, 18, and said he was a resident of the heavily Latino community about 85 miles west of San Antonio. The governor said Ramos walked into Robb Elementary School in Uvalde around 11:30 a.m. Central time and opened fire.
USA TODAY is providing general details about the shooter to inform how mass attacks are often planned and carried out, particularly with respect to how weapons and targets are selected. These details give authorities and the public information that could help citizens spot future mass shooters and even prevent them.
THURSDAY: Live updates on Texas school shooting
Tuesday’s attack was the deadliest shooting at a U.S. grade school since a gunman killed 20 children and six adults at Sandy Hook Elementary in Newtown, Connecticut, almost a decade ago. The Texas shooting comes just 10 days after a gunman in body armor killed 10 Black shoppers and workers at a supermarket in Buffalo, New York, in what authorities say was a racist attack.
Here's what we know about the shooter in Tuesday's deadly attack:
BLOODSHED SINCE SANDY HOOK: Uvalde school shooting among deadliest school attacks in past 10 years
LATEST INFO IN YOUR INBOX: Our Daily Briefing newsletter delivers the news to you
Officials say the gunman acted alone
Texas authorities on Wednesday said they were still seeking answers about a possible motive and what sparked the attack from a man who had no criminal adult record and no known mental health history.
But at a news conference in Uvalde on Wednesday with other state and law enforcement officials, Gov. Abbott said the gunman shot his grandmother in the face prior to attacking the school. Abbott called him a “demented person.”
Roughly 30 minutes before the attack, the gunman issued several chilling communications on social media, Abbott said.
A spokesman for Meta, the parent company of Facebook, said on Twitter that the messages that Abbott described were private one-to-one messages.
The shooter had lived with his 66-year-old grandmother since March, officials said. She survived the shooting, seeking help from neighbors while police were called. She was airlifted and was being treated for her injuries at a hospital in San Antonio, law enforcement officials said.
The gunman took his grandmother's truck and crashed it just outside of Robb Elementary school, Abbott said. Around 11:30 a.m., he took an AR-15-style rifle and a backpack with him and went to enter the school. Another rifle was later discovered in his truck, according to a briefing given to lawmakers.
The shooter was wearing a plate carrier but not ballistic armor, according to a briefing that state Sen. John Whitmire said he received. Police were not pursuing the gunman before he crashed, he said.
At the school, the shooter first encountered school resource officers but made it inside the school through a back door, officials said. He walked down hallways before entering a classroom.
Police from several agencies converged on a classroom and burst in. A U.S. Border Protection agent shot and killed the gunman, a senior Department of Homeland Security official told USA TODAY. The agent was shot in the foot or lower leg when confronting the gunman, and was treated a local hospital for his injuries, the DHS official said.
The school district's police chief, Pete Arredondo, said the gunman acted alone.
In all, 19 children were killed along with two faculty members, Abbott said.
"I consider this person to have been pure evil," Abbott said.
Gunman believed to have dropped out of Uvalde High School before buying guns
The attacker was reported to have been a student at Uvalde High School before dropping out, Abbott said.
The high school, part of the same school district as Robb Elementary where the shooting took place, enrolls about 1,100 students, according to the school district. 91% of students in the district are Hispanic, and almost 80% are economically disadvantaged, the district said.
Uvalde is home to roughly 16,000 people, about 85 miles west of San Antonio and 75 miles from the Mexican border. More than 80% of the city's population is Latino, according to the U.S. Census Bureau.
NOT JUST UVALDE, TEXAS: Gunfire on school grounds is at historic highs in the US
Texas Department of Public Safety Director Steve McCraw said on Wednesday that the gunman recently purchased two semi-automatic rifles on separate dates, and a department spokesman later clarified to USA TODAY that the purchases were made on May 17 and 20.
He also purchased 375 rounds of 5.56 ammunition, and what appears to be seven 30-round magazines were inside the school, Whitmire said.
On Wednesday, investigators said they were working to try to discover a catalyst for the shooting. Law enforcement officers maintained a guard on a house where the gunman is believed to have shot his grandmother.
Wendy Arrillos, 40, a convenience store worker who lives three doors down, said she’s known the grandmother casually for more than five years, but had never seen the shooter before his attack left the small community reeling.
“It’s a small town. We all know each other,” Arrillos said.
'WE ALL JUST HAVE TO SAY THAT'S ENOUGH': How cable news covered the Uvalde, Texas, school shooting
'SO MANY CRUSHED SPIRITS': Biden addresses nation after Texas school shooting
More information about shooter's online activity, possible warning signs emerges
The gunman in the attack sent messages to a 15-year-old girl in Germany just prior to the attack, CNN reported Wednesday. The outlet said it reviewed screenshots of messages and spoke with the girl, who said she met the assailant online.
On Monday the gunman told her he received a package of ammunition. Asked what he was going to do with it, he replied, "just wait for it."
The Washington Post spoke with childhood friends of the attacker, who described him becoming increasingly isolated and erratic in his behavior.
Investigators also have been scrutinizing an Instagram account that apparently belonged to Ramos. In the days before the shooting, posts featured a photo of a hand holding an ammunition magazine and another photo of two AR-15-style rifles. The account asked another Instagram user to share the latter photo with her 10,000 followers; she declined, saying it was “scary” and she barely knew him.
Instagram declined to answer questions about the postings.
Experts in extremism who study mass shooters were still trying to establish Wednesday whether Ramos had any connections to hate groups or whether he was involved with online communities that promote violence.
Meta, the parent company of Instagram, confirmed it is working with law enforcement to review an account that appears to belong to the gunman.
NBA COACH'S STERN MESSAGE: Steve Kerr gives emotional speech after school shooting; LeBron James, more react
Contributing: Trevor Hughes, Kevin McCoy, Josh Meyer and Sarah Eames, USA TODAY; Tony Plohetski, Austin American-Statesman; Eric Ferkenhoff, USA TODAY Network; The Associated Press
This article originally appeared on USA TODAY: Texas school shooter identified: What we know about motive