One filled with explosives and left inside a car is about to destroy anything and everything around it.
You can watch as the bomber detonates the device.
Eyewitness News was invited to a secret location in South Jersey as agents with the ATF wrapped up a week-long training event with bomb squads and emergency responders from all over the state.
"They have to be the bomber. They have to be the bomber so they can figure out what was blown up," said Special Agent Tim Willson, ATF.
Special Agent Tim Willson is one of the explosive experts there.
He and the others are building bombs and blowing up cars so that their students can have a scene to investigate.
Terrorism is the main focus there.
The bombs are placed, the range is cleared, and the call is made.
First up was a pipe bomb.
It doesn't look like much from where Eyewitness News was, but when you look up close, anyone inside this car would have been killed.
Next up was a more powerful device causing more destruction.
And finally, it was time for the big one!
The scenario: a suicide bomber sets off his bomb.
You can see from the damage that he clearly doesn't make it, but the real scary part is what happens behind it. A second bomb was placed so when the first responders arrive, it kills as many people as possible.
Just like we saw in the Boston bombings, this device was packed to do maximum damage.
"It was channeled so it came up like this and then out, and you can see from all of the marks here we put bb's in it. They went everywhere," Willson said.
The students then moved in and they marked evidence and begin to investigate.