Texas school shooter used shotgun, pistol in deadly assault

Christal Hayes | USA TODAY

Show Caption Hide Caption Texas student: 'All we heard was run, run' A tenth-grade student and her mother described the tense moments during and after a deadly high school shooting in Santa Fe, Texas on Friday. Dakota Shrader says she heard alarms at her school and then people yelling to run. (May 18)

The attack at a Texas high school Friday echoed the all-too-familiar horrors Americans are accustomed to seeing on the news. But two details set it apart from the list of other recent deadly attacks: explosives and weapons used.

Texas Gov. Greg Abbott in Texas says the gunman, Dimitrios Pagourtzis, who was a student at Santa Fe High School, used two firearms: a shotgun and .38 caliber revolver, both of which he got from his father. Ten were left dead, mostly students.

The guns may have slowed down the gunman’s deadly rampage because they have a slower firing rate than firearms used in other recent mass shootings, such as the AR-15. Abbott said it was unclear whether Pagourtzis' father knew that the weapons were missing.

High-powered rifles such as the AR-15 can be fired more than twice as fast as most handguns. The standard magazine for an AR-15 holds 30 rounds, allowing a shooter to continue firing uninterrupted for longer, making the weapon more lethal than other firearms, though clearly the use of any gun can be deadly, especially a shotgun at close range.

The shooter also left behind a number of explosive devices both inside and outside the school, including a Molotov cocktail found in a vehicle and CO2 device found in a home.

An attacker using explosives isn't unheard of during mass shootings, but does pose a new threat to law enforcement attempting to clear the school, vehicles and the accused gunman's home.

One of the more notable attacks that involved explosives was at Columbine High School in 1999. Eric Harris and Dylan Klebold planted two large propane bombs inside the school's cafeteria that failed to detonate. They also used a diversion explosive outside the school.

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The devices Abbott described that authorities found on Friday were more juvenile. A molotov cocktail is fairly easily crafted by placing flammable liquid in a bottle and igniting it with a wick.

CO2 explosives are created using a cartridge filled with highly pressurized CO2 and replacing it with gunpowder or some other type of flammable substance. It's also ignited by a fuse.

Authorities on Friday cautioned residents to be on alert for any additional devices planted in the area.

Texas had recently been rattled by a series of package bombs in March. In total, five explosives left two people dead and several others injured in and around the Austin area. Mark Anthony Conditt, 23, killed himself by detonating a bomb inside his vehicle as authorities centered on him.

The explosives were particularly threatening as some had triggers such as a tripwire.

Explosives were also found in San Bernardino, Calif. after the attack in 2015 that left 14 dead in an office building. Investigators found about a dozen pipe bombs and a workshop inside the home of Syed Rizwan Farook and Tashfeen Malik.

The gunman in the 2012 movie theater shooting in Aurora, Colo. also left behind an array of bombs in his apartment after killing 12 people. More than 20-homemade devices were scattered around James Holmes' apartment, boobytrapping it for law enforcement.

More: Texas high school student: 'You hear boom, boom, boom, and I just ran as fast as I could'

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Many of the deadliest mass shootings in recent years involved high-powered rifles, notably AR-15 styled rifles. But far fewer have featured shotguns or a revolver as the primary killing weapon. In Friday's attack, it's likely the weapons may have kept the death toll from rising.

The list of mass shootings that feature high-powered rifles include some of the deadliest: Las Vegas; Orlando, Fla.; Sutherland Springs, Tx.; Parkland, Fla.; and Aurora, Colo.

But there have been attacks that only featured shotguns or other handguns. In 2013, Aaron Alexis, a contractor with the Navy with mental illness, purchased a shotgun and used the single firearm to kill 12 people at the Washington Navy Yard in 2013.

Other shootings, including the deadly attack at Virginia Tech included less lethal weapons. Student Seung-Hui Cho used two pistols to kill 32 people in 2007.

Follow Christal Hayes on Twitter: Journo_Christal