Anatomy of a Bomb: Inside the Explosive Device Used in NYC Blast

Inside Edition tested a pressure-cooker bomb at a range in New Mexico.

New details about the bomb that caused panic in the streets of a New York City neighborhood after it detonated Saturday night have emerged.

The bomb contained a legal explosive called Tannerite, normally used for shooting practice, according to former NYPD Bomb Squad Detective Kevin Barry.

Read: Bombing Suspect Ahmad Khan Rahami Nabbed After Shootout; Was Found Dozing in N.J. Doorway

“It's commercially available through the internet,” he told Inside Edition. "Someone sets out a target in the woods, goes a considerable distance, if they hit the target, there's a small explosion."

A second explosive device, a pressure cooker bomb, was found four blocks away before it could go off. A flip cell phone was attached as a trigger.

The explosive device was taken away by police in a bomb-proof trailer.

Barry says it's disturbingly easy to improvise a bomb like the one found on the Manhattan street Saturday night.

“You could spend a week going through the online material that is available to everybody,” he said.

The blast here in the Chelsea neighborhood of Manhattan sent a Dumpster flying. Some experts think the bomb went off inside the Dumpster, which would have deflected some of the impact of the blast, possibly saving many lives.

Pressure cooker bombs were used to deadly effect in the 2013 Boston Marathon explosions.

Inside Edition recently tested the force of a pressure cooker bomb at a range in New Mexico.

A deafening explosion rocked the desert and bits of shrapnel flew in all directions. A charred pot and a bent lid were all that was left of the device, but somehow, plywood walls surrounding the bomb remained intact.

New Mexico Tech vice president and physics professor Van Romero explained the devastating effects of flying shrapnel to Inside Edition.

He said, "It's not likely to kill a lot of people, if you are very close to it you will obviously be killed, but it will throw fragments a long way."

Read: Mayor Calls Manhattan Blast 'Intentional Act' After Exploding Dumpster Injures Dozens

Romero added that the plywood around the bomb remained intact because: "Everything shot straight up. In Boston, the bomb was more than likely placed on its side, shooting shrapnel out in the street."

Detective Barry says it's a miracle no one was killed given that the bomber had one chilling goal.

He said: “They took the main charge, they surround it with ball bearings and BBs. They're enhancing the kill power of the device.”

Watch: New Yorkers Run From Explosion in Dumpster That Injured 29