The Sacramento County Sheriff's Department sent a helicopter and several deputies last weekend to investigate, following multiple reports of the explosions. According to the authorities, the booms are likely caused by illegal fireworks with the concussive force of up to half a stick of dynamite.

Residents mostly seem to agree with the authorities, at least according to the Facebook page created for them to share their experiences; although not every person’s report is consistent with that theory.

"I live at Madison & Kenneth. Our neighborhood experienced these loud booms, about two years ago," one resident reported. "Sometimes we'd lose power afterwards, then [Sacramento Municipal Utility District (SMUD)] showed up one day with a crew. I heard another BOOM which sounded like it was in my front yard, when I went outside I found all my neighbors out looking around. Apparently the noise was coming from the High Voltage lines, but after SMUD left we never heard the BOOMS again."

Other residents have speculated whether it could be a meteorological phenomenon or some sort of test from nearby Beale Air Force Base.

Reports of mysterious booms—sometimes accompanied by flashes of light and/or minor tremors—have been on the rise worldwide since 2017, continuing throughout 2018 and into this year. The booms have been reported across the United States in Alabama, Arizona, Arkansas, California, North and South Carolina, Colorado, Georgia, Idaho, Illinois, Indiana, Kentucky, Michigan, Missouri, New Jersey, New York, Pennsylvania, Tennessee, Texas, Utah, Washington, and Wisconsin; as well as in the countries of Russia, Denmark, England, and Australia.

Meteors and other natural events—such as frost quakes—remain popular explanations for the booms, and bolide meteors were blamed for mystery booms in California, Michigan, and Washington in 2018. However, no blanket explanation covers every occurrence of a mystery boom and many cases go unexplained entirely.

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