Marco Island, Florida - Is it a bomb? Is it a plane? Or is it a sonic boom? Loud bangs have Islanders looking to the sky with wonder.

Comment: How about a meteorite exploding in the upper atmosphere?

Occasional loud booms had Marco Islanders and others in Southern Collier County wondering what the noise was Wednesday and Thursday.

Marco Island city officials received several calls about the banging noises, said Public Information Coordinator Lisa Douglass.

Police Chief Thom Carr said officers heard the noise too, but they weren't sure what they were.

Chief Meteorologist Jim Farrell of WINK-TV said his newsroom has received a few calls from Collier County residents reporting booms as well.

"Some residents even thought it was an earthquake. We checked into it and there were no earthquakes in our area," Farrell reported.

He said WINK news reporters believed the noise and vibrations might be coming from a construction site.

More likely it was a sonic boom. A sonic boom refers to the shocks caused by the supersonic flight of an aircraft. Sonic booms generate enormous amounts of sound energy, sounding much like an explosion.

While the military may not confirm or deny any jets in the area, residents are reporting Air Force sightings off the Gulf coast the last two days, Douglass said.

"Usually these jets stay out over the Gulf of Mexico, but when there is cold air in place the sound and vibration can travel quite a bit," Farrell said.