TOTOWA, N.J. (CBSNewYork) — It started off as a well-kept secret, but the explosions and helicopters ended up giving it away.

Members of the U.S. Department of Defense were conducting training recently in a New Jersey neighborhood, and the result was plenty of residents with frayed nerves, CBS2’s Dick Brennan reported Wednesday.

MORE: NYC, 2 Other Cities Sue Department Of Defense Over Gun Check Reporting

Cellphone video captured the moment a helicopter flew above Totowa. There was excitement in the photographer’s voice, but that’s because the video was taken on the second night of action.

“I have never seen anything like this before,” resident Michael Melograno said.

Melograno took the video from his backyard on Rutherford Court. The chopper was flying right above the North Jersey Developmental Center, which is under construction.

“There was a Blackhawk helicopter flying right over here,” Melograno says on the clip.

He can now laugh and even brag about what happened, but in the heat of the moment he said his entire block was petrified.

“I was really scared. I had no idea what was going on,” Melograno said.

At around 10 p.m. on April 16, the community was rocked by piercing explosions.

“We were scared about that, you know? It happened at night time,” resident Mauricio Gallardo said.

“First it was explosions and then the chopper was so low that our house was vibrating,” resident Larry Pizzichetta added.

Most of the residents on the block came running outside in panic. John Emmolo said his daughter called 9-1-1 to find out what was happening, but got a short answer.

“They said, ‘Well, you have to talk to state police about it,'” Emmolo said.

Eventually, they learned members of the U.S. Armed Forces were training in secret for three nights. So CBS2 went to both local and state police to find out why the residents weren’t informed.

Neighbors said they should have been informed, and next time they are hoping they get a head’s up before they have to look up.

Both local and state police wouldn’t go on camera, and CBS2 is still waiting for a call back from the Department of Defense.