A bright burst of light illuminated the horizon over western Washington state Wednesday night, followed by a loud boom that shook the ground, according to several reports, leaving both residents and officials puzzled.
Local officials in Grays Harbor County received hundreds of calls about the incident, the cause of which remains a mystery.
The county's Division of Emergency Management said it contacted the National Weather Service in Seattle, which said there was not a severe weather event in the area at the time of the reported "ground shaking, loud boom and flash of light in the sky."
The Washington State Duty Officer also contacted the Federal Aviation Administration and the Western Air Defense Sector, but both said they did not have any problems on their end.
"There was no earthquake. There are no reports of explosions or crashes on the ground," the Grays Harbor County's Division of Emergency Management said in a statement Wednesday night. "We will continue our investigation of the incident."