Mysterious booming sound mystifies residents of Bradley, McMinn, Polk Counties
Authorities in at least three counties spent part of the day Thursday trying to track down the source of a loud boom.
We heard from viewers about this as well, right after it happened at about 11:30 a.m.
They were mainly from northern Bradley County, but there were also reports of people hearing and feeling the boom in Polk and McMinn Counties.
We verified with several chemical plants - including Wacker and Olin - that nothing happened there.
Hours later, authorities in both Bradley in McMinn Counties said they still haven't determined what happened.
They have ruled out things like an earthquake.
We'll keep you posted as we learn more.