Mysterious boom rattles several South Carolina communities

May 25 (UPI) -- Authorities in South Carolina are investigating the cause of a mysterious boom that woke residents and shook homes in multiple cities, and officials said they do not believe an earthquake was involved.

Residents in the Lowcountry area of the state reported the loud noise about 8:40 a.m. Tuesday, and at least one resident managed to capture the boom on a doorbell camera in Mount Pleasant.

The South Carolina Emergency Management Division said the cause of the sound is under investigation. Similar incidents in the past have been caused by earthquakes, but officials said they do not believe that to be the case for the most recent boom.

"Getting several questions about a large boom/rumble in the Charleston area earlier this morning," emergency management officials tweeted. "We have no reports of any earthquakes at this time. We're working to determine the source."

The U.S. Geological Survey confirmed no earthquake activity was detected, and NASA officials said no spacecraft were due to reenter the atmosphere at the time of the sound.

Some residents postulated the boom may have been the result of a military training exercise the U.S. Coast Guard had earlier announced would be held north of Charleston, but a Coast Guard spokesman said officials were unable to find a link between the exercise and the boom heard Tuesday.

The American Meteor Society said there were no witness accounts of fireballs at the time of the sound, and local weather forecasters said they were unable to identify any potential meteors on radar.

Emergency Management Division officials said the investigation is ongoing.