Mystery boom in Cape Coral,  FL
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A loud boom - that some say shook them to their core - has people in Cape Coral concerned, confused, and curious about the cause.

"All of a sudden there was this huge boom," said JoAnn Navarre. "My daughter and I both screamed, and we jumped."

Navarre lives on NW 31st Street in Cape Coral. She said the commotion happened around 6 p.m. Sunday.

"We thought maybe something hit the house; something hit nearby. We didn't know if something exploded; we thought people were hurt," Navarre said.

After it happened, she went outside to inspect and found many of her neighbors doing the same thing.

One of those neighbors was Stephanie Berkau, who said she not only heard it but felt it.

"You feel it to your bones, you could feel it in your body. It wasn't just external things; you felt it to the core," Berkau said.

NBC2 reached out to the City of Cape Coral, its police department, and a couple of Air Force bases in the state, and none could give a solid answer as to what caused this. Though Cape Coral police didn't know exactly what it was, they said it was likely a sonic boom.

Berkau said she'd like a warning next time if it was planned.

"Make the public aware, so they're not thinking, God forbid, there was a terror attack, [or] somebody trying to bomb us because that's what it sounded like ... a bomb."