New Orleans attacker tried to use high explosive that could have killed hundreds

The New Orleans truck attacker built two bombs using what investigators believe was an explosive so powerful that they could have sprayed shrapnel hundreds of yards and potentially killed or wounded hundreds of people. 

The bombs did not detonate on New Year’s Day. But experts say the devices Shamsud-Din Jabbar built with a compound believed to be RDX would have had devastating effects were it not for an amateurish blunder.

“As horrible as it is that he killed and injured all of these people, it could have been exponentially worse in the truest sense of the term had these devices actually functioned,” said Scott Sweetow, a retired executive with the Bureau of Alcohol, Tobacco, Firearms and Explosives and former director of the FBI’s Terrorist Explosive Device Analytical Center. “You’d be looking at literally hundreds of casualties.”

A bomb made with RDX going off in a tourist section of New Orleans would be the equivalent of multiple hand grenades thrown into a crowded street, Sweetow said. 

 “It would have been absolute carnage,” he added.

The bombs failed to go off because Jabbar used the wrong device to detonate the explosive, federal law enforcement officials have said. 

He used an electric match, which could set off a typical pipe bomb made with powder explosives. But a compound like RDX is vastly more difficult to set off. It’s considered a high explosive material, meaning it won’t detonate without a primary explosion occurring near it — initiated by what’s known as a blasting cap or detonator. 

Three explosive experts interviewed by NBC News said they were baffled that Jabbar seemingly knew to use a little-known compound more powerful than TNT but not how to get it to detonate.

“It just doesn’t make sense,” said Tony May, a retired ATF agent who also worked as an Army explosive enforcement officer in Afghanistan.

By using RDX, experts say Jabbar was mimicking the tactics of terrorist groups operating in the Middle East, where it is far easier to obtain. The vast majority of bomb attacks in the U.S. involve powder explosives that are simpler to make and far less powerful. 

“The thing to me that is most troubling is that other people may try to do this now,” said David Hyche, a former ATF agent who is now the chief of police in Calera, Alabama. 

Jabbar, 42, an Army veteran from Texas who was inspired by the Islamic State terrorist group, killed 14 people and injured dozens when he drove a rented pick-up truck down a blocked-off section of Bourbon Street at about 3:15 a.m. on Jan. 1. After carving a three-block path of destruction, he was shot dead in a gunbattle with police.

Roughly an hour earlier, Jabbar had put his homemade bombs inside two coolers and placed them on Bourbon Street, the famous party area in the heart of the French Quarter. It remains unclear if he resorted to the truck attack because the bombs failed to detonate or if using the truck to kill was always a part of his plan. Jabbar also had a handgun and a semiautomatic rifle with a privately made silencer, according to law enforcement officials.

At his home in Houston, investigators found explosive materials that field tests identified as RDX. They also found explosive materials at a home he rented in New Orleans that tests initially identified as R-Salt, an explosive similar in chemical makeup to RDX. But the ATF said Sunday that it now believes that more thorough lab tests will show that it, too, was RDX.

RDX is not easy to obtain in the United States. A military-grade explosive, it’s also used for specialized purposes by demolition and mining companies and can only be purchased with a federal license. Criminals have been known to get their hands on stolen RDX, but multiple experts told NBC News they suspect Jabbar synthesized it himself — a time-consuming and highly dangerous endeavor. 

That theory is based on footage shot inside Jabbar’s Houston home by the New York Post, which showed a property receipt listing items the federal investigators had seized, including common lab materials and precursor chemicals like acetone, sulfuric acid and potassium nitrate.

“There is no indication he had the requisite knowledge to do this on his own,” said Sweetow, the former ATF and FBI official. “So he would have had to have either received information from outside sources, or done significant research on the Internet.”

Terrorist groups in the Middle East have bombmakers who synthesize their own high explosives but that is rarely seen in the U.S. The two most well-known cases of that are the 1993 World Trade Center bombing and the bombing of the Oklahoma City federal building in 1995. 

Had Timothy McVeigh, the Oklahoma City bomber, used RDX, the attack would have been even more catastrophic, experts said. 

“You wouldn’t have had one building blown down,” said Hyche, the former ATF agent-turned-police chief. “You’d have multiple buildings blown down.”

Building a bomb with RDX is also more challenging and more dangerous.

“Most people don’t have the skillset for that, and they’re not willing to follow a recipe,” Sweetow said. “People kill themselves all the time trying to make this stuff because they’re not that skilled of a chemist.”

The retired ATF officials said investigators are almost certainly looking into how Jabbar gained the knowledge to use a compound like RDX. Was he working directly with a member of ISIS or another terror group? Or did he find instructions in an obscure corner of the internet?

“If someone told him how to do this stuff, where are they?” Sweetow said. “And is this part of a trend?”

This story first appeared on NBCNews.com. More from NBC News:

• Chemical used for explosives found in Texas storage locker linked to New Orleans attacker, authorities say
• What we know about the victims of the New Orleans truck attack
• The driver in the New Orleans attack was an Army veteran from Texas