Dozens of individuals in a small Tennessee city reported hearing mysterious booms Wednesday night.
Spring Hill 911 director Brandi Smith told The Tennessean that the emergency agency started receiving reports at around 10 p.m. of "loud booms."
She later heard the mysterious noise herself.
"The first one sounded like a tree or something like that falling and the second one sounded like firecrackers," she told The Tennessean. "It was an awesome experience."
An ambulance and firefighters were sent to an area where the noises were thought to be coming from, Smith said.
"People were trying to figure out what it was. And some were scared," she told The Tennessean.
[sharequote align="center"]"People were trying to figure out what it was. And some were scared."[/sharequote]
"It was a deep boom, like it was under the ground," resident Keith Mohr echoed. "It sounded like when they were blasting on Reserve Boulevard."
Others turned to Facebook to report the noise.
"Very Loud!!!" wrote Renee Spicer. "Thought a ice coated big tree fell on the house....WOW!!"
"It was crazy! I went and grabbed the gun! The dogs were going crazy ... it shook my house," said Shannon Lewis.
According to Smith, the leading theory was that the noises were cryoseismic booms, or mini explosions in the ground triggered by cold weather.
The National Weather Service in Nashville also weighed in on the mystery, appearing to agree with the theory.
The agency, however, still asked those who heard the boom to contact them with more info.
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