Texas Gov. Greg Abbott demanded swift justice for the gunman who killed 10 people at Santa Fe High School and vowed to come up with ways to prevent school massacres.

Although he's assembling a panel to discuss solutions, Abbott indicated during a visit to the high school this weekend that he already has a few ideas. Among them are installing metal detectors on campuses and conducting mental health screenings and social media checks on students.

Abbott said that beginning Tuesday, he will gather lawmakers, experts and citizens to hear testimony. The Republican said the roundtable will listen to survivors of the killings at Santa Fe High and a church in Sutherland Springs, as well as gun-rights supporters and gun-control advocates.

Texas Lt. Gov. Dan Patrick, Gov. Greg Abbott, and Texas first lady Cecilia Abbott pause and reflect after laying flowers at Santa Fe High School in Santa Fe, Texas Sunday May 20, 2018. On Friday morning May 18, 10 people were killed and 13 were injured after a shooting at Santa Fe High School. (Andy Jacobsohn / Staff Photographer)

One of the most obvious changes that Texas can bring about is to improve school safety, Abbott said, noting that many in Santa Fe had asked him for that. After laying flowers at the high school on Sunday, the governor spoke about metal detectors and screening students for mental health problems.

Abbott said schools should consider screening students' social media accounts for threats or troubling behavior.

"We need to do that," he said, adding that Dimitrios Pagourtzis, the suspect in the Santa Fe shooting, had pictures on his Facebook page of a T-shirt that read, "Born to kill."

Abbott said Friday that he'd been planning to roll out several proposals for new gun laws in Texas before the shooting, including "speeding up background checks" and keeping guns away from people "who pose immediate danger."

He made no mention of those proposals during his visit to the high school Sunday.

"We're praying for all the kids who attend this school, for the nightmare that they have lived through," he said. "But we know that beginning this next week, it's time to go to work."

Lt. Gov. Dan Patrick, the Republican who leads the state Senate, also supported the roundtable.

"I can assure you that whatever answers we find from the experts, from citizens, and from parents and all those involved, it will be Senate Bill 1," he said. "It'll be our first priority."

Patrick told reporters that the problem is society, not its weapons.

"This is not about guns," he said. "The smart things we can do about background checks and other issues we'll address, and we'll do. This is about us as a culture and a nation."

He excoriated the video game industry, which he said propagates violence, and denounced a loss of faith and religion in society.

But he also urged gun owners to be responsible. Police say the shooter used his father's shotgun and revolver to kill eight students and two teachers after barging into an art class Friday.

"The responsibility of gun owners who have guns at home: lock up your guns," he said. "I'm a gun owner. We have a responsibility to be sure our guns are safe at home. That's where gun control starts — at home. Let's make sure no kid gets his hands on a gun."

After being mocked for suggesting that schools should reduce the number of entrances and exits, Patrick tried to clarify his earlier comments. He said there would be enough exits to safely enter and exit a building, but "no one should be able to come in those doors" without authorities watching.

He pointed to security at schools in Israel that have security guards that "deter, detect and deny" potential threats.

During an interview Sunday with ABC News, Patrick argued for arming teachers and said reducing the number of guns in the U.S. wouldn't make the country safer.

Guns "are a part of who we are as a nation; it is our Second Amendment," he told news anchor George Stephanopoulos. "You know, it talks about a well-run militia, the Second Amendment. Our teachers are part of that well-run militia, by the way. It's guns that also stop crimes."

Texas Lt. Gov. Dan Patrick advocates arming teachers in wake of deadly Texas shooting.



"It talks about a well-run militia – the 2nd Amendment – our teachers are part of that well-run militia, by the way." https://t.co/2InagT0td3 pic.twitter.com/7ZW4dwgXEm — ABC News (@ABC) May 20, 2018

The text of the Second Amendment refers to "a well regulated militia."

Fred Guttenberg, whose 14-year-old daughter Jaime was killed February at Stoneman Douglas High School in Parkland, Fla., was visibly angry after hearing Patrick's comments on Stephanopoulos' show.

The father, who was also interviewed by Stephanopoulos, said he had gone to Dallas to protest the National Rifle Association convention in May and pointed to how the event had promoted a gun made to look like a cellphone. The NRA has aggressively fought calls for gun control since a student killed 17 people in Parkland.

"Regarding the Second Amendment, I am pretty confident the framers of our Constitution did not sit around predicting the day where we would have guns that looked like cellphones," Guttenberg said.

He condemned Patrick's stance.

"I'm sorry — that man —those were idiotic comments," Guttenberg said. "I am raging right now."

Mourners embrace following a memorial for one of the slain students, Sabika Sheik, at Sabireen Masjid in Stafford, Texas on Sunday May 20, 2018. Sheikh, a foreign exchange student from Pakistan was one of ten killed on May 18 after a shooting at Santa Fe High School. (Andy Jacobsohn / Staff Photographer)

Among those wounded Friday was John Barnes, a school resource officer who had retired from the Houston Police Department.

Houston police Chief Art Acevedo said in a Facebook post that he had shed tears of sadness, pain and anger and that he had hit "rock bottom."

He had harsh words for politicians who, in his view, are not doing enough to address gun violence.

"This isn't a time for prayers, and study and inaction, it's time for prayers, action and the asking of God's forgiveness for our inaction (especially the elected officials that ran to the cameras today, acted in a solemn manner, called for prayers, and will once again do absolutely nothing)."

The Houston Chief of Police, @ArtAcevedo just posted this on his FB page. pic.twitter.com/CQpo8rumBP — Michael Skolnik (@MichaelSkolnik) May 19, 2018

Acevedo continued to criticize other officials during an interview with CBS' Face the Nation.

"People at the state level and the federal level in too many places in our country are not doing anything other than offering prayers," the police chief said.

Acevedo went on, calling for authorities across the country to consider tougher penalties against people who don't properly secure their firearms.

"When there's skin in the game for all weapons owners including myself, I think that people will have a different outlook," he said. "And so we've got to make sure that everyone stores them in a responsible manner and that there are significant penalties when they fail to do so and people die as a result of those — of that failure."

Graduating high school seniors are recognized during worship service at Arcadia First Baptist Church in Santa Fe, Texas Sunday May 20, 2018. Gov. Greg Abbott, Lt. Gov. Dan Patrick, and others were in attendance at the service. (Andy Jacobsohn / Staff Photographer)

In Texas, it's a Class C misdemeanor to leave an unsecured firearm in a place where a child "younger than 17 years of age" can have access to it. The crime becomes a Class A misdemeanor if the child harms or kills himself or someone else.

Pagourtzis, the suspect in the Santa Fe slayings, is 17. Classmates and Santa Fe parents who know him described him to The Washington Post as a quiet and reclusive kid who regularly wore a trench coat and who was well liked on the football team.

Like the Texas lieutenant governor, incoming NRA President Oliver North indicated that a "culture of violence" was responsible for the recurring slaughters at American high schools. He also pointed to Ritalin, a drug used to treat attention deficit hyperactivity disorder, or ADHD.

"The disease in this case isn't the Second Amendment," North told Fox News host Chris Wallace. "The disease is youngsters who are steeped in a culture of violence. They have been drugged in many cases. Nearly all of these perpetrators are male and they are young teenagers in most cases."

He continued: "And they have come through a culture where violence is commonplace. All you need to do is turn on the TV, go to a movie. If you look at what has happened to the young people, many of these young boys have been on Ritalin since they were in kindergarten."

Incoming @NRA President Oliver North says: "If school shield had been in place, far less likely that would have happened. "The disease in this case isn’t the 2nd amendment, the disease is youngsters who are steeped in a culture of violence, they've been drugged in many cases," pic.twitter.com/TrFFG0jHK0 — FoxNewsSunday (@FoxNewsSunday) May 20, 2018

North said it's less likely the massacre at Santa Fe High would have happened if it had participated in an NRA program called School Shield. He said the program gives schools a free assessment that looks at entrances, exits and the ease with which a student might be able to sneak in a firearm.

"You are not going to fix it by taking away the rights of law-abiding citizens," he said. "You've got to take it away to harden the place sufficiently, that those kids are safe inside the door. If that means five metal detectors getting in and out of the high school, you get five metal detectors."

Santa Fe High was already a hardened target, according to The Post. Two police officers guard the school, which reportedly had won a statewide award for its security plan. The school district had agreed last fall to arm teachers and staff members under a Texas law that allows "school marshals" to have guns on campus — though Santa Fe was still working on implementation.

"My first indication is that our policies and procedures worked," Santa Fe ISD board of trustees president J.R. "Rusty" Norman told The Post. "Having said that, the way things are, if someone wants to get into a school to create havoc, they can do it."

Acevedo told National Public Radio on Sunday that the governor's office hadn't called him about participating in the roundtable.

The police official said time will tell whether Abbott is sincere about his demands for change.

"Proof is in the pudding," Acevedo told NPR. "We'll see. I made my statement about elected officials. I hope that every single one that went to cameras and gave interviews that day, I hope they put egg on my face and prove me wrong."

Abbott called on Texans to observe a moment of silence at 10 a.m. Monday in memory of those slain in Santa Fe.