Prosecutors say they will seek the death penalty for the North Texas man suspected of fatally gunning down 22 people and injuring dozens of others at an El Paso Walmart Saturday.
El Paso County records Sunday showed that 21-year-old Patrick Wood Crusius, of Allen, was booked at the downtown jail in the Texas border city. There was no immediate indication that he had an attorney.
Crusius graduated from Plano Senior High School in 2017 and lived in the North Dallas suburb of Allen.
Jacob Wilson, a former classmate who graduated with the suspect in 2017, said he remembered the suspect as someone who kept to himself.
"Very introverted person and he definitely showed that in school," Wilson recalled. "He would show up and not really say anything."
Wilson said he never kept in touch with Crusius and his only interaction with the suspect was in the English class they had together senior year.
"After thinking back on it, he was picked on and bullied and all sorts of things. He was also the kind of kid you didn't want to work with because he was so strong minded in what he thought," Wilson said.
During a Sunday news conference, El Paso County District Attorney Jaime Esparza said the state of Texas plans to seek the death penalty.
"We have never seen this in our community. We pride ourselves on the fact that we are so safe. This community is rocked and shocked and saddened by what happened yesterday," said Esparza.
A Justice Department official said the federal government is treating the El Paso shooting as a "domestic terrorist" case. U.S. Attorney John Bash said Sunday the federal government is also investigating the attack as a possible hate crime. It was designed "to intimidate a civilian population to say the least," he said.
Law enforcement sources said they believed Crusius posted a document online just before the shooting. El Paso Police Chief Greg Allen confirmed Sunday they had attributed the screed directly to Crusius.
Sources familiar with Crusius' writings characterized the message as anti-immigration, anti-government and anti-large corporations.
When asked whether the shooting was a hate crime, Allen said "it's beginning to look more solidly like that is the case."
Allen said Crusius was cooperating and forthcoming with information.
The FBI said three warrants related to the suspected shooter were executed in the Dallas area. Law enforcement officials were seen going in and out of an Allen home Saturday that is Crusius' last listed address.
The FBI told NBC 5 Sunday morning agents had finished going through the home and law enforcement has cleared the scene. An FBI spokesperson said they were there at the family's invitation. She added the FBI's role is simply to assist in the murder investigation.
Police in Allen said they had few past interactions with Crusius, their contact with him "can be described as limited at best."
Allen police said Crusius was reported as a juvenile runaway in 2014 but returned home roughly a half-hour later. He was also among eight students on a school bus involved in a minor crash in 2016 that resulted in no injuries.
Allen police said their last involvement with Crusius came in March when he reported a false residential alarm at his grandparents' home.
The family living in the home is requesting privacy. Neighbors said it's an older couple who have lived there for many years. No one seemed to know or recognize the 21-year-old.
They all said it was a shock to see the investigation begin so close to home after watching the coverage out of El Paso.
"It's unreal. It's unreal to see FBI, DEA, ATF in this area. I mean it's a beautiful neighborhood. So many people work hard to get to this place and it's just … when you think of all the families in this neighborhood and what they're having to endure going through this. And my heart is with the kid's family, whoever his caretakers is or were. I'm sure there day's just as bad as anyone else's today. I can't imagine what they're feeling. I can't imagine what the lives of the families impacted by today's events are feeling," Craig LeBlanc said.
"The individual who did this shooting today did not wake up this morning and decide, 'I'm going on a killing spree.' He has thought about this for weeks, months, possibly years. He has fantasized about it [and] has planned it out," former FBI agent Greg Shaffer told NBC 5 Saturday. "So the FBI and local law enforcement are looking into social media and interviewing his work colleagues, his classmates, friends and family to try and find the motivation behind this heinous act."
Collin College confirmed a student named Patrick Crusius was enrolled from 2017 through this spring.
“We are saddened and horrified by the news of the shooting today in El Paso, Texas. A student by the name of Patrick Crusius attended Collin College from fall 2017 through spring 2019.
Collin College is prepared to cooperate fully with state and federal authorities in their investigation of this senseless tragedy. We join the governor and all Texans in expressing our heartfelt concern for the victims of the shooting and their loved ones.”
NBC 5's Chris Blake, Tim Ciesco, Elvira Sakmari, Allie Spillyards and Diana Zoga contributed to this report.