Anchorage - Southcentral Alaska authorities didn't have any immediate cause for a loud booming noise heard Thursday night and reported by Channel 2 viewers, but seemed to rule out sonic booms from aircraft in responses Friday.

Reports of the sounds were posted on Channel 2's Facebook page Thursday evening by people ranging from Eagle River to the Mat-Su Valley. Some reports placed the phenomenon between 8 p.m. and 10 p.m. Thursday, with Channel 2's Late Edition airing a brief update on the reports. Viewers' descriptions of the sound varied, but those who heard it generally agreed that it was a strong and persistent noise.

"I live in Peters Creek and I heard several loud noises outside and then muted the television," Channel 2 viewer Rachel Lee wrote. "After about a minute of silence, there was a rumble and my chandelier started to shake. I thought it might have been an earthquake but I looked online and there weren't any listed at that time; it was 8:05 p.m."

"About the only thing I can compare it to is someone going down a dirt road really fast," viewer Deb Spaulding wrote. "(I)t was that sort of rumble."

"I was in the garage and I heard it. It (lasted) for a while," wrote viewer Michelle Thomas Hanks. "At first I thought it was the wind until I stepped outside... My (neighbor's kids) looked for what was making that loud noise and they could not see anything just kept hearing the loud noise."

John Pennell, Joint Base Elmendorf-Richardson's chief of media operations, says the base wasn't flying any of its supersonic fighter jets capable of causing sonic booms Thursday night, with only subsonic C-17 Globemaster III transports flying until 9:30 p.m.

"Although they are loud, I don't think anybody's going to mistake them for a sonic boom," Pennell said.

Val Jokela, a Federal Aviation Administration community-affairs representative in Anchorage, says the FAA's regional operations center received no noise complaints overnight.

Law enforcement agencies were similarly stymied by the reports, with Anchorage Police Department spokesperson Dani Myren saying no noise complaints were listed for Thursday or Friday. Dispatchers on duty overnight didn't relay any reports of the booms to the next shift, which came on duty at 7 a.m.

Alaska State Troopers spokesperson Megan Peters says troopers also had no noise complaints from the region, with AST dispatchers also not relaying any updates during a 6 a.m. shift change.

"There wasn't anything there big enough for them to pass on or be told about," Peters said.

The Alaska Volcano Observatory had no reports Friday on the noise itself or any volcanic activity that may have caused it. The West Coast and Alaska Tsunami Warning Center's latest listed earthquake was a magnitude 4.6 temblor on Dec. 24, centered 40 miles northwest of Valdez.

The National Weather Service forecast office in Anchorage also didn't have any possible causes, saying there was some shower activity in the area Thursday but nothing more severe in terms of weather conditions.

With no immediate answers on the matter Lee, the Peters Creek viewer, echoed the confusion of many people about the source of the noise.

"It's strange no one knows what caused it," Lee wrote.