Violent video games and films, abortion and divorce are behind the US school shooting epidemic – but not guns, according to the lieutenant governor of Texas, where 10 people were shot dead on Friday.

America has “devalued life”, Dan Patrick said, adding that “it’s not about the guns, it’s about us”.

A 17-year-old student at Santa Fe High School is being held on suspicion of murder following the massacre at the school in which eight pupils and two teachers were killed. A police officer remains in critical condition in hospital after “a lot of rounds” were exchanged with the shooter.

Authorities said Dimitrios Pagourtzis used a shotgun and .38 handgun belonging to his father, who had acquired them legally.

Speaking to CNN on Sunday, Mr Patrick called for “gun control at home” and said the weapons should be kept out of children’s reach.

But on ABC’s This Week, he blamed cultural currents for the ongoing violence.

He said: “Should we be surprised, in this nation? We have devalued life, whether it’s through abortion, whether it’s the break-up of families, through violent movies and particularly violent video games, which now outsell movies and music.

“Psychologists and psychiatrists will tell you that students are desensitised to violence, may have lost empathy for their victims by watching hours and hours of violent video games.

“Ninety-seven per cent of teenagers, according to psychiatrists and psychologists, watch video games and 85 per cent of those are violent games.”

Texas shooting: scene at Santa Fe high school Show all 15 1 /15 Texas shooting: scene at Santa Fe high school Texas shooting: scene at Santa Fe high school Santa Fe High School staff react as they gather in the parking lot of a gas station The Galveston County Daily News via AP Texas shooting: scene at Santa Fe high school An active shooter incident was reported at Santa Fe High School in Texas KTRK-TV ABC13 via AP Texas shooting: scene at Santa Fe high school People embrace outside the Alamo Gym where students and parents wait to reunite following a shooting at Santa Fe High School Houston Chronicle via AP Texas shooting: scene at Santa Fe high school Law enforcement officers responding at Santa Fe High School HCSO via Reuters Texas shooting: scene at Santa Fe high school Santa Fe High School student Dakota Shrader is comforted by her mother Susan Davidson following a shooting at the school Stuart Villanueva/The Galveston County Daily News via AP Texas shooting: scene at Santa Fe high school School staff members sit in a school bus to be transported to another school The Galveston County Daily News via AP Texas shooting: scene at Santa Fe high school A Santa Fe Police officer consoles others after the shooting The Galveston County Daily News via AP Texas shooting: scene at Santa Fe high school Emergency personnel and law enforcement officers respond to claims that an active shooter was reported on campus KTRK-TV ABC13 via AP Texas shooting: scene at Santa Fe high school Police officers work a check point in front of Santa Fe High School The Galveston County Daily News via AP Texas shooting: scene at Santa Fe high school A woman prays in the grass outside the Alamo Gym where parents wait to reunite with their kids following a shooting at Santa Fe High School Houston Chronicle via AP Texas shooting: scene at Santa Fe high school Santa Fe High School freshman Caitlyn Girouard, center, hugs her friend outside the Alamo Gym Houston Chronicle via AP Texas shooting: scene at Santa Fe high school A Pearland Police armored vehicle stands in front of Santa Fe High School The Galveston County Daily News via AP Texas shooting: scene at Santa Fe high school Emergency responders from multiple agencies work at the scene The Galveston County Daily News via AP Texas shooting: scene at Santa Fe high school In this image taken from video law enforcement officers respond to a high school near Houston after an active shooter was reported on campus, Friday, May 18, 2018, in Santa Fe, Texas. The Santa Fe school district issued an alert Friday morning saying Santa Fe High School has been placed on lockdown. (KTRK-TV ABC13 via AP) KTRK-TV ABC13 via AP Texas shooting: scene at Santa Fe high school In this image taken from video law enforcement officers respond to a high school near Houston after an active shooter was reported on campus, Friday, May 18, 2018, in Santa Fe, Texas. The Santa Fe school district issued an alert Friday morning saying Santa Fe High School has been placed on lockdown. (KTRK-TV ABC13 via AP) KTRK-TV ABC13 via AP

Mr Patrick did not provide a source for the statistics.

In addition, he said – both on ABC and during an address at the weekend – that schools should be made into “hard targets” with a reduced number of entrances and exits.

He added: “We still have this gun debate about whether teachers should be armed or not. I believe, and the parents and the students I’ve talked to in Santa Fe since Friday, believe they should be.”

Pressed on whether Texas should consider tighter regulation of firearms, Mr Patrick said: “The problem is multi-faceted, it’s not any one issue. We have to look at our culture of violence, our violent society.

Texas official responds to Santa Fe shooting by calling for fewer school doors

“Our Facebook, our Twitter, the bullying of adults on adults, of children on children. We have to look at ourselves – it’s not about the guns, it’s about us.”

Nevertheless, Texas’s governor Greg Abbott promised to convene a panel of experts and advocates for both gun rights and gun control to discuss what needed to change to protect schoolchildren.

He laid lilies under the sign at Santa Fe High School on Sunday, then spoke to the media about possible solutions which he said included “hardening” schools to protect against attacks, employing metal detectors and monitoring students’ social media accounts.

He promised “swift and meaningful action” to ensure “that we will build a pathway to reforms so that other students will not have to live through a nightmare like these students had to go through”.

Mr Abbott is a strong proponent of gun rights.

On Sunday Mr Patrick also rejected a comparison between the US and other countries where gun deaths in schools were said to be less likely, and firearms less accessible. “There are many variables in all these countries,” he said.

Pleas for tougher gun laws have followed several major mass shootings in schools and elsewhere in recent years, from Sandy Hook in 2012 to Las Vegas last year and Parkland, Florida, in February.

Survivors of the Parkland shooting launched the “March for our Lives” to push for new laws.

On Sunday, the National Rifle Association’s incoming president blamed the stimulant drug Ritalin for school shootings, although there was no indication that it or any other substance was being probed in this case.

“The disease is youngsters who are steeped in a culture of violence,” said the NRA’s Oliver North, a former US Marine colonel convicted in 1989 over the Iran-Contra affair.

He added: “They’ve been drugged in many cases. Nearly all of these perpetrators are male, and they’re young teenagers in most cases, and they’ve come through a culture where violence is commonplace.

“All we need to do is turn on a 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. Now I am certainly not a doctor. I’m a marine.”