PITTSBURGH (KDKA) -- It's a mystery not only in this area, but in communities across the country.
They sound like loud explosions, except there's never any damage. So, what is really going on?
Imagine you're sitting on your front porch when out of nowhere a cataclysmic explosion goes off. You see a bright light, you feel the force, and then, it goes away. Then, when emergency responders go to investigate, they can't find a thing.
Well, it happened in Fayette County recently and it's happening around the United States.
For Michelle Wiltrout, what happened around 7:45 p.m. Monday is something she'll never forget.
"All I heard was a large explosion," said Wiltrout. "I thought something blew up or a bad car wreck."
Whatever it was, numerous resident around Connellsville heard and felt it, too. For some, it was so intense it rattled the foundations of their homes and knocked pictures off their walls.
Mysterious massive explosions are not exclusive to Fayette County. The phenomena are worldwide and nothing new.
"Back in the 1960s we used to call them 'sky quakes,'" says Stan Gordon, who is a researcher in the field of the unexplained phenomena. "In more recent years, there seems to be an increase in these type of reports."
Explanations abound - sonic booms, meteorites, kids blowing things up - but not all of these earth-shaking, window-rattling events are resolved.
"In March of last year, I received and I know other sources received numerous reports of a very loud shaking and a boom that covered many communities in Fayette County," Gordon said. "Around the same time as the big boom were some unusual lights in the sky and then later a lot of people reporting a lot of helicopter activity in the area. I've never heard an explanation for that one."
Those who have experienced these enormous, mystery explosions say they're unnerving, whatever they are.
"I don't know, but it's scary because it's too close to home," said Wiltrout.
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