Santa Barbara, California, U.S. - A series of jolts or "booms" as some viewers have described them are sending nervous jitters through the Tri-counties.

The first one hit at 9:34am in the Santa Barbara area followed by at least a half dozen more over the next hour. People have been calling into the KEYT newsroom from Thousand Oaks to Morro Bay saying they felt them.

The San Luis Obispo County Sheriff's Dept. released a statement at 10:42am explaining that it confirmed through various state and federal agencies that there has been no seismic activity, but it may be activity caused by military aircraft flying over our area.

The U.S. Geological survey website shows a 2.6 magnitude quake hit the Cherry Valley area in Riverside County at 9:34am, but it seems unlikely that would be the source of the jolts.

Vandenberg Air Force base is not reporting any military activity. Staff Sgt. Riendeau at the base said in a phone interview they are "looking into the issue to find out what's going on."

Steve Walter, a seismologist with the USGS in Menlo Park, told KEY News in a phone interview that the jolts appear to be happening in the atmosphere, something he calls "air phase". He said many of the phone calls he received so far are from the Vandenberg, Lompoc, Diablo Canyon and Santa Maria areas. He said the reports he has heard are similar to what the Navy does in Northern California when they blow up older explosives. The blasts can be felt for up to 100 miles away.

KEY News will post the latest on this story as we get it and on KEY News tonight.