A series of loud booms have been rattling a neighborhood in Peabody, Massachusetts, for months, shaking the ground and startling homeowners.
The explosion sounds, which started in February, have prompted both state and city officials to work together to try to determine the cause.
"We all have gas, and we don't want to see anything happen to what happened in the Merrimack Valley a while ago," said Tracy Valletti, who lives on Emerson Street.
A couple of small earthquakes that hit the region in recent weeks — one on July 25 and another on Aug. 4 — could explain some of the disturbances.
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The July earthquake measured a magnitude of 1.4, according to the U.S. Geological Survey. The one that followed 10 days later registered a 1.2, according to records.
But homeowners said they heard the bizarre sounds both before and after those events.
Dr. John Ebel, senior research scientist at Boston College's Weston Observatory, said smaller, undetected earthquakes are likely to blame for the loud, mysterious noises.
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"Once every few years, we get what we call and earthquake swarm," he said. "If we have an earthquake that's only detected on say two or three stations, the automated systems may not be good enough to pick that up, and I suspect that that’s what’s happening."
In a statement on Monday, the Massachusetts Emergency Management Agency said it "is coordinating with officials from the City of Peabody, the USGS and the Weston Observatory to discuss recent earthquakes and other reports of sounds in the Peabody area."
"Do I think the end of the world's coming? No, I don't," said Barry Silverman, who also lives on Emerson Street. "It's just a weird feeling."